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Building an Inexpensive Oracle RAC 10g Release 1 on Linux - (WBEL 3.0 / FireWire)
by Jeff Hunter, Sr. Database Administrator
Contents
Overview
For those who simply want to become familiar with Oracle10g RAC, this article
provides a low cost alternative to configure an Oracle10g RAC system using
commercial off the shelf components and downloadable software. The estimated cost
for this configuration could be anywhere from $1200 to $1800. This system
will consist of a dual node cluster (each with a single processor), both running Linux
(White Box Enterprise Linux 3.0 Respin 1 or Red Hat Enterprise Linux 3) with a shared disk storage based on IEEE1394
(FireWire)
drive technology.
(Of course, you could also consider building a
virtual cluster
on a VMware Virtual Machine, but the experience won't quite be the same!)
Please note, that this is not the only way to build a low cost Oracle10g RAC
system. I have seen other solutions that utilize an implementation based on SCSI
rather than FireWire for shared storage. In most cases, SCSI will cost more than
a FireWire solution
where a typical SCSI card is priced around $70 and an 80GB external SCSI drive
will cost around $700-$1000. Keep in mind that some motherboards may already include
built-in SCSI controllers.
It is important to note that this configuration should never be
run in a production environment and that it is
not supported by Oracle or any other vendor. In a production
environment, fiber channel—the high-speed serial-transfer interface that can
connect systems and storage devices in either point-to-point or switched
topologies—is the technology of choice.
FireWire offers a low-cost alternative to fiber channel for testing
and development, but it is not ready for production.
Although in past experience I have used raw partitions for storing
files on shared storage, here we will make use of the Oracle Cluster File System (OCFS) and
Oracle Automatic Storage Management (ASM). The two Linux servers will be configured as follows:
The Oracle Cluster Ready Services (CRS) software will be installed to
/u01/app/oracle/product/10.1.0/crs on each of the nodes
that make up the RAC cluster. However, the CRS software requires that two
of its files, the
"Oracle Cluster Registry (OCR)" file and the "CRS Voting Disk" file
be shared with all nodes in the cluster. These two files will
be installed on the shared storage using Oracle's Cluster File System (OCFS).
It is possible (but not recommended by Oracle) to use RAW devices for these files, however,
it is not possible to use ASM for these CRS files.
The Oracle10g R1 Database software will be installed into a separate
Oracle Home; namely /u01/app/oracle/product/10.1.0/db_1.
All of the Oracle physical database files (data, online redo logs, control files, archived redo logs),
will be installed to different partitions of the shared drive being
managed by Automatic Storage Management (ASM).
Oracle10g Real Application Cluster (RAC) Introduction
At the heart of Oracle10g RAC is a shared disk subsystem. All nodes in the
cluster must be able to access all of the data, redo log files, control
files and parameter files for all nodes in the cluster. The data disks must
be globally available in order to allow all nodes to access the database. Each
node has its own redo log file(s) and UNDO tablespace, but the other nodes must be able to
access them (and the shared control file) in order to recover that node in the event of a system failure.
Not all clustering solutions use shared storage. Some vendors use an approach
known as a federated cluster, in which data is spread across several machines
rather than shared by all. With Oracle10g RAC, however, multiple nodes use the same
set of disks for storing data. With Oracle10g RAC, the data files, redo log files, control files,
and archived log files reside on shared storage on raw-disk devices, a NAS, ASM, or on a
clustered file system. Oracle's approach to clustering leverages the collective
processing power of all the nodes in the cluster and at the same time provides
failover security.
The biggest difference between Oracle RAC and OPS is the addition of Cache
Fusion. With OPS a request for data from one node to another required the
data to be written to disk first, then the requesting node can read that
data. With cache fusion, data is passed along a high-speed interconnect
using a sophisticated locking algorithm.
Pre-configured Oracle10g RAC solutions are available from vendors such as
Dell, IBM and HP for production environments. This article, however,
focuses on putting together your own Oracle10g RAC environment for development
and testing by using Linux servers and a low cost shared disk solution; FireWire.
Shared-Storage Overview
A less expensive alternative to fibre channel is SCSI. SCSI technology provides
acceptable performance for shared storage, but for administrators and developers who
are used to GPL-based Linux prices, even SCSI can come in over budget, at around
$1,000 to $2,000 for a two-node cluster.
Another popular solution is the Sun NFS (Network File System) found on a NAS. It can be used for
shared storage but only if you are using a network appliance or something similar.
Specifically, you need servers that guarantee direct I/O over NFS, TCP as the transport protocol,
and read/write block sizes of 32K.
The shared storage that will be used for this article is based on
IEEE1394 (FireWire) drive technology. FireWire is able to offer a low-cost alternative
to Fibre Channel for testing and development, but should never be used in a production
environment.
FireWire Technology
The following chart shows speed comparisons of the various types of disk interface.
For each interface, I provide the maximum transfer rates in kilobits (kb), kilobytes (KB),
megabits (Mb), megabytes (MB), gigabits (Gb), and gigabytes (GB) per second.
As you can see, the capabilities of IEEE1394 compare very favorably with
other disk interface and network technologies that are currently available today.
Hardware & Costs
Each Linux server should contain two NIC adapters.
The Dell Dimension includes an integrated 10/100 Ethernet adapter that
will be used to connect to the public network. The second NIC adapter
will be used for the private interconnect.
The following is a list of FireWire I/O cards that contain the correct chipset,
allow for multiple logins, and should work with this article (no guarantees however).
FireWire I/O cards with chipsets made by VIA or TI are known to work.
Each Linux server should contain two NIC adapters.
The Dell Dimension includes an integrated 10/100 Ethernet adapter that
will be used to connect to the public network. The second NIC adapter
will be used for the private interconnect.
The following is a list of FireWire I/O cards that contain the correct chipset,
allow for multiple logins, and should work with this article (no guarantees however).
FireWire I/O cards with chipsets made by VIA or TI are known to work.
The following is a list of FireWire drives (and enclosures) that contain the correct chipset,
allow for multiple logins, and should work with this article (no guarantees however):
Each node in the RAC configuration will need to connect to the
shared storage device (the FireWire hard drive). The FireWire hard drive
will come supplied with one FireWire cable. You will need to purchase
one additional FireWire cable to connect the second node to the
shared storage. Select the appropriate FireWire cable that is compatible
with the data transmission speed (FireWire 400 / FireWire 800) and the
desired cable length.
Used for the interconnect between int-linux1 and int-linux2. A question I often
receive is about substituting the Ethernet switch (used for interconnect
int-linux1 / int-linux2) with a crossover CAT5 cable. I would not recommend this.
I have found that when using a crossover CAT5 cable for the
interconnect, whenever I took one of the PCs down, the
other PC would detect a "cable unplugged" error, and thus
the Cache Fusion network would become unavailable.
Click on the following images for
a larger view of the Maxtor OneTouch external drive:
As we start to go into the details of the installation, it should be
noted that most of the tasks within this
document will need to be performed on both servers. I will indicate at the beginning
of each section whether or not the task(s) should be performed on both
nodes or not.
Install White Box Enterprise Linux 3.0
Also, before
starting the installation, ensure that the FireWire drive (our
shared storage drive) is NOT connected to either of the two servers.
Although none of this is mandatory, it is how I will be
performing the installation and configuration in this article.
After downloading and burning the WBEL images (ISO files) to CD,
insert WBEL Disk #1 into the first server (linux1 in this example), power it on,
and answer the installation screen prompts as noted below. After completing
the Linux installation on the first node, perform the same Linux installation
on the second node while substituting the node name linux1 for linux2
and the different IP addresses were appropriate.
Boot Screen
If there were
a previous installation of Linux on this machine, the next screen
will ask if you want to "remove" or "keep" old partitions. Select the option
to [Remove all partitions on this system]. Also, ensure that the
[hda] drive is selected for this installation. I also keep the
checkbox [Review (and modify if needed) the partitions created] selected.
Click [Next] to continue.
You will then be prompted with a dialog window asking if you really
want to remove all partitions. Click [Yes] to acknowledge this warning.
First, make sure that each of the network devices are checked
to [Active on boot]. The installer may choose
to not activate eth1.
Second, [Edit] both eth0 and eth1 as follows. You may choose
to use different IP addresses for both eth0 and eth1 and that
is OK. If possible, try to put eth1 (the interconnect) on
a different subnet than eth0 (the public network):
eth0:
eth1:
Continue by setting your hostname manually. I used
"linux1" for the first node and "linux2" for the second.
Finish this dialog off by supplying your gateway and
DNS servers.
When the system boots into Linux for the first time, it will prompt
you with another Welcome screen. The following wizard allows you to
configure the date and time, add any additional users, testing the
sound card, and to install any additional CDs. The only screen I care
about is the time and date. As for the others, simply run through
them as there is nothing additional that needs to be installed (at this point
anyways!). If everything was successful, you should now be presented with the
login screen.
First, make sure that each of the network devices are checked
to [Active on boot]. The installer will choose not
to activate eth1.
Second, [Edit] both eth0 and eth1 as follows:
eth0:
eth1:
Continue by setting your hostname manually. I used
"linux2" for the second node.
Finish this dialog off by supplying your gateway and
DNS servers.
Network Configuration
Each node should have one static IP address for the public network
and one static IP address for the private cluster interconnect. The
private interconnect should only be used by Oracle to transfer
Cluster Manager and Cache Fusion related data. Note that Oracle does
not support using the public network interface for the interconnect.
You must have one network interface for the public network and another
network interface for the private interconnect. For a production RAC implementation,
the interconnect should be at least gigabit or more and only be used by Oracle.
The easiest way to configure network settings in Red Hat Enterprise Linux 3 is with the program
Network Configuration. This application can be started from the command-line
as the "root" user account as follows:
Using the Network Configuration application, you need to configure
both NIC devices as well as the
Our example configuration will use the following settings:
It's all about availability of the application.
When a node fails, the VIP associated with it is supposed to be automatically
failed over to some other node. When this occurs, two things happen.
This means that when the client issues SQL to the node that is
now down, or traverses the address list while connecting, rather than
waiting on a very long TCP/IP time-out (~10 minutes), the client receives
a TCP reset. In the case of SQL, this is ORA-3113. In the case of
connect, the next address in tnsnames is used.
Without using VIPs, clients connected to a node that died will often wait
a 10 minute TCP timeout period before getting an error.
As a result, you don't really have a good HA solution without using VIPs.
Source - Metalink: "RAC Frequently Asked Questions" (Note:220970.1)
Oracle strongly suggests to adjust the default and maximum send buffer size
(SO_SNDBUF socket option) to 256 KB, and the default and maximum receive
buffer size (SO_RCVBUF socket option) to 256 KB.
The receive buffers are used by TCP and UDP to hold received data until it is read by
the application. The receive buffer cannot overflow because the peer is not allowed to
send data beyond the buffer size window. This means that datagrams will be discarded if
they don't fit in the socket receive buffer. This could cause the sender to overwhelm
the receiver.
The above commands made the changes to the already running O/S.
You should now make the above changes permanent (for each reboot) by adding the following lines
to the /etc/sysctl.conf file for each node in your RAC cluster:
If UDP ICMP is blocked or rejected by the firewall, the CRS software will crash after several minutes
of running. When the CRS process fails, you will have something similar to the following
in the <machine_name>_evmocr.log file:
Obtaining and Installing a proper Linux Kernel
While FireWire drivers already exist for Linux, they often do not support shared storage.
Normally, when you logon to an O/S, the O/S associates the driver to a specific drive
for that machine alone. This implementation simply will not work for our RAC
configuration. The shared storage (our FireWire hard drive) needs to be accessed
by more than one node. We need to enable the FireWire driver to provide nonexclusive
access to the drive so that multiple servers - the nodes that comprise the cluster -
will be able to access the same storage. This is accomplished by removing the bit mask
that identifies the machine during login in the source code. This results in allowing nonexclusive access
to the FireWire hard drive. All other nodes in the cluster login to the same drive
during their logon session, using the same modified driver, so they too also have
nonexclusive access to the drive.
Our implementation describes a dual node cluster (each with a single processor), each server
running White Box Enterprise Linux. Keep in mind that the process of installing the
patched Linux kernel will need to be performed on both Linux nodes.
White Box Enterprise Linux 3.0 (Respin 1) includes kernel 2.4.21-15.EL #1. We will need to download the Oracle
Technet Supplied 2.4.21-27.0.2.ELorafw1 Linux kernel from the following URL:
http://oss.oracle.com/projects/firewire/files.
The following is a listing of my /etc/grub.conf file before and then after
the kernel install. As you can see, the install that I did put in another
stanza for the 2.4.21-27.0.2.ELorafw1 kernel. If you want, you can chance
the entry (default) in the new file so that the new kernel will be the default
one booted. By default, the installer keeps the default kernel (your original one) by setting
it to default=1. You should change the default value to zero (default=0)
in order to enable the new kernel to boot by default.
It is vital that the parameter sbp2_exclusive_login of the Serial Bus
Protocol module (sbp2) be set to zero to allow multiple hosts to
login to and access the FireWire disk concurrently. The second line ensures
the SCSI disk driver module (sd_mod) is loaded as well since
(sbp2) requires the SCSI layer. The core SCSI support module
(scsi_mod) will be loaded automatically if (sd_mod)
is loaded - there is no need to make a separate entry for it.
Power on the FireWire drive.
Finally, power on each Linux server and ensure to boot each machine into the new kernel.
In most cases, the loading of the FireWire stack will already
be configured in the /etc/rc.sysinit file. The commands
that are contained within this file that are responsible for loading
the FireWire stack are:
For this configuration, I was performing the above procedures on
both nodes at the same time. When complete, I shutdown both machines, started
linux1 first, and then linux2. The following commands and
results are from my linux2 machine. Again, make sure that you run
the following commands on all nodes to ensure both machine can login to the
shared drive.
Let's first check to see that the FireWire adapter was successfully detected:
From the above output, you can see that the FireWire drive I have can
support concurrent logins by up to 3 servers. It is vital that you have a
drive where the chipset supports concurrent access for all nodes within the RAC cluster.
One other test I like to perform is to run a quick fdisk -l from
each node in the cluster to verify that it is really being picked up by
the O/S. Your drive may show that the device does not contain a valid partition table,
but this is OK at this point of the RAC configuration.
In older versions of the kernel, I would need to run the
rescan-scsi-bus.sh script
in order to detect the FireWire drive. The purpose of this script
was to create the SCSI entry for the node by using the following
command:
With Red Hat Enterprise Linux 3, this is no longer required and the disk should be detected automatically.
You may also want to unplug any USB devices connected to the server. The system
may not be able to recognize your FireWire drive if you have a USB device attached!
Create "oracle" User and Directories
For this example, I used:
You can check the available space in /tmp by running the following
command:
Creating Partitions on the Shared FireWire Storage Device
The following table lists the individual partitions that will
be created on the FireWire (shared) drive and what files
will be contained on them.
Create All Partitions on FireWire Shared Storage
After each machine is back up, run the "fdisk -l /dev/sda" command on each
machine in the cluster to ensure that they both can see the partition table:
Configuring the Linux Servers for Oracle
Throughout this section you will notice that there are several different ways to
configure (set) these parameters. For the purpose of this article, I will
be making all changes permanent (through reboots) by placing all commands
in the /etc/rc.local file. The method that I use will echo
the values directly into the appropriate path of the /proc file system.
# free
- OR -
# cat /proc/swaps
- OR -
# cat /proc/meminfo | grep MemTotal
As root, make a file that will act as additional swap space, let's say about 300MB:
Now we should change the file permissions:
Finally we format the "partition" as swap and add it to the swap space:
Oracle makes use of shared memory for its Shared Global Area (SGA) which is an area of
memory that is shared by all Oracle backup and foreground processes. Adequate sizing of
the SGA is critical to Oracle performance since it is responsible for holding the database
buffer cache, shared SQL, access paths, and so much more.
To determine all shared memory limits, use the following:
Setting SHMMAX
You can determine the value of SHMMAX by performing the following:
Setting SHMMNI
You can determine the value of SHMMNI by performing the following:
Setting SHMALL
To determine all semaphore limits, use the following:
Setting SEMMSL
Oracle recommends setting SEMMSL to the largest PROCESS instance parameter
setting in the init.ora file for all databases on the Linux system plus 10.
Also, Oracle recommends setting the SEMMSL to a value of no less than 100.
Setting SEMMNI
Oracle recommends setting the SEMMNI to a value of no less than 100.
Setting SEMMNS
Oracle recommends setting the SEMMNS to the sum of the PROCESSES
instance parameter setting for each database on the system, adding the largest
PROCESSES twice, and then finally adding 10 for each Oracle database on the system.
Use the following calculation to determine the maximum number of semaphores
that can be allocated on a Linux system. It will be the lesser of:
Setting SEMOPM
The semop system call (function) provides the ability to do operations for multiple
semaphores with one semop system call. A semaphore set can have the maximum
number of SEMMSL semaphores per semaphore set and is therefore recommended
to set SEMOPM equal to SEMMSL.
Oracle recommends setting the SEMOPM to a value of no less than 100.
Setting Semaphore Kernel Parameters
Use the following command to determine the maximum number of file handles
for the entire system:
Oracle recommends that the file handles for the entire system be set to at least 65536.
Use the following command to determine the value of ip_local_port_range:
To make these changes, run the following as root:
We could reboot at this point to ensure all of these parameters are set in the
kernel or we could simply "run" the /etc/sysctl.conf file by running the
following command as root. Perform this on each node of the cluster!
Configuring the "hangcheck-timer" Kernel Module
Much more information about the
hangcheck-timer project
can be found
here.
These values need to be available after each reboot of the Linux server. To do this, make
an entry with the correct values to the /etc/modules.conf file as follows:
It is only out of pure habit that I continue to include a modprobe
of the hangcheck-timer kernel module in the /etc/rc.local file. Someday I will get
over it, but realize that it does not hurt to include a modprobe of
the hangcheck-timer kernel module during startup.
So to keep myself sane and able to
sleep at night, I always configure the loading of the hangcheck-timer kernel module on
each startup as follows:
Now, to test the hangcheck-timer kernel module to verify it is picking up the
correct parameters we defined in the /etc/modules.conf file, use the modprobe
command. Although you could load
the hangcheck-timer kernel module by passing it the appropriate parameters
(e.g. insmod hangcheck-timer hangcheck_tick=30 hangcheck_margin=180),
we want to verify that it is picking up the options we set in the
/etc/modules.conf file.
To manually load the hangcheck-timer kernel module and verify it is using the
correct values defined in the /etc/modules.conf file, run the following command:
Configuring RAC Nodes for Remote Access
First, let's make sure that we have the rsh RPMs installed on
each node in the RAC cluster:
To enable the "rsh" and "rlogin" services, the "disable" attribute in the /etc/xinetd.d/rsh
file must be set to "no" and xinetd must be reloaded.
This can be done by running the following commands on all nodes in the cluster:
I will typically rename the Kerberos version of rsh so that the normal
rsh command will be used. Use the following:
You should now test your connections and run the rsh command from the node that will be performing
the Oracle CRS and 10g RAC installation. I will be using the node linux1 to perform all installs so this
is where I will run the following commands from:
All Startup Commands for Each RAC Node
In this section, I provide all of the commands, parameters, and entries that
have been discussed so far that will need to be included in the startup scripts
for each Linux node in the RAC cluster. For each of the startup files below,
I indicate in blue the entries that should be included
in each of the startup files in order to provide a successful RAC node.
/etc/modules.conf
/etc/sysctl.conf
/etc/hosts
/etc/hosts.equiv
/etc/grub.conf
/etc/rc.local
Checking RPM Packages for Oracle10g R1
Installing and Configuring Oracle Cluster File System (OCFS)
In this article, I will be using OCFS Release 1.0 to store
the two files that are required to be shared by CRS. (These will be the only two files
stored on the OCFS.) This release of OCFS (release 1.x) for Linux
does NOT support using the file system for a shared Oracle Home
install (The Oracle database software). This feature will be available in a future
release of OCFS for Linux, possibly release 2.x. In this article, I will be installing
the Oracle database software to a separate $ORACLE_HOME directory locally on each Oracle Linux
server in the cluster.
In release 1.x for Linux, OCFS only supports the following types
of files:
See the following document for more information on Oracle Cluster File System Release 1.0
(including Installation Notes) for Red Hat Linux:
Installing OCFS
The next step is to load the ocfs.o kernel module.
Like all steps in this section, run the following
command on all nodes in the cluster as the root user account:
Other problems can occur when using FireWire. If you are still
having troubles loading and verifying the loading of the
ocfs module, try the following on all nodes that
are having the error as the "root" user account
Thanks again to
Werner Puschitz for coming up
with the above solutions!
Earlier in this document, we created
the directory /u02/oradata/orcl
under the section Create Mount Point for OCFS / CRS.
This section contains the commands to create and mount the directory to be used
for the Cluster Manager - /u02/oradata/orcl.
To create the file system, we use the Oracle
executable /sbin/mkfs.ocfs. For the purpose
of this example, I run the following command only from
linux1 as the root user account:
The following is a list of the options available with the
mkfs.ocfs command:
First, here is how to manually mount the OCFS file system from the
command-line. Remember that this needs
to be performed as the root user account:
First, let's use the mount command to ensure that
the new file system is really mounted. This should be performed
on all nodes in the RAC cluster:
Next, use the ls command to check ownership. The permissions should be
set to 0775 with owner "oracle" and group "dba".
If this is not the case for all nodes in the cluster, then it
is very possible that the "oracle" UID (175 in this example) and/or the
"dba" GID (115 in this example) are not the same across all nodes.
Installing and Configuring Automatic Storage Management (ASM) and Disks
ASM was introduced in Oracle10g and is used to alleviate the DBA from
having to manage individual files and drives. ASM is built into the Oracle kernel and
provides the DBA with a way to manage thousands of disk drives 24x7 for both
single and clustered instances of Oracle. All of the files and directories to be used
for Oracle will be contained in a disk group. ASM automatically performs
load balancing in parallel across all available disk drives to prevent hot spots and
maximize performance, even with rapidly changing data usage patterns.
I start this section by first discussing the ASMLib libraries and its associated driver for Linux
plus other methods for configuring ASM with Linux.
Next, I will provide instructions for downloading the ASM drivers (ASMLib Release 1.0) specific to
our Linux kernel. (These libraries/driver are available from OTN)
Lastly, I will install and configure the ASM drivers while finishing off the
section with a demonstration of how I created the ASM disks.
If you would like to learn more about the ASMLib, visit
http://www.oracle.com/technology/tech/linux/asmlib/install.html
The next section, "Methods for Configuring ASM with Linux", discusses the two methods for using ASM on Linux
and is for reference only!
When I first started this article, I wanted to focus on using ASM for all
database files.
I was curious to see how well ASM worked (load balancing / fault tolerance)
with this test RAC configuration. There are two
different methods to configure ASM on Linux:
In this article, I will be using the "ASM with ASMLib I/O" method. Oracle states
(in Metalink Note 275315.1) that "ASMLib was provided to enable ASM I/O to Linux
disks without the limitations of the standard UNIX I/O API". I plan on performing
several tests in the future to identify the performance gains in using ASMLib. Those
performance metrics and testing details are out of scope of this article and therefore
will not be discussed.
Before discussing the installation and configuration details of ASMLib, I thought it would be
interesting to talk briefly about the second method "ASM with Standard Linux I/O".
If you were to use this method, (which is a perfectly valid solution, just not the method
we will be implementing in this article), you should be
aware that Linux does not use RAW devices by default. Every Linux RAW device you want to
use must be bound to the corresponding block device using the RAW driver. For example,
if you wanted to use the partitions we created in the
"Creating Partitions on the Shared FireWire Storage Device"
section, (/dev/sda2, /dev/sda3, /dev/sda4), you would need to
perform the following tasks:
Like I mentioned earlier, the above example was just to demonstrate that there
is more than one method for using ASM with Linux. Now let's move on to
the method that will be used for this article, "ASM with ASMLib I/O".
Here is a list of those partitions we created:
The last task in this section it to create the ASM Disks.
Downloading Oracle10g R1 RAC Software
In this section, we will be downloading and extracting the required software from Oracle
to only one of the Linux nodes in the RAC cluster - namely linux1. This is the machine
where I will be performing all of the installs from. The Oracle installer will copy the required
software packages to all other nodes in the RAC configuration using the remote access method we
setup in the section "Configuring RAC Nodes for Remote Access".
Login to one of the nodes in the Linux RAC cluster as the "oracle" user account.
In this example, I will be downloading the required Oracle software to linux1 and
saving them to "/u01/app/oracle/orainstall/crs"
and "/u01/app/oracle/orainstall/db".
Extract the Cluster Ready Services (CRS) package as follows:
Then extract the Oracle10g Database Software:
Installing Oracle Cluster Ready Services (CRS) Software
So, what exactly is the Oracle CRS responsible for?
The CRS contains all of the cluster and database configuration metadata along
with several system management features for RAC. It allows the DBA to
register and invite an Oracle instance (or instances) to the cluster. During normal
operation, CRS will send messages (via a special ping operation) to all nodes
configured in the cluster - often called the heartbeat. If the heartbeat fails
for any of the nodes, it checks with the CRS configuration files (on the shared disk)
to distinguish between a real node failure and a network failure.
After installing CRS, the Oracle Universal Installer (OUI)
used to install the Oracle10g database software (next section) will automatically
recognize these nodes. Like the CRS install we will be performing in this section,
the Oracle10g database software only needs to be run from one node. The OUI will
copy the software packages to all nodes configured in the RAC cluster.
Oracle provides an excellent note on Metalink entitled:
"CRS and 10g Real Application Clusters - (Note: 259301.1)".
From that note, here are some the key facts about CRS and Oracle10g RAC
to consider before installing both software components:
Login as oracle
Unset ORACLE_HOME
Verify Environment Variables on linux1
Verify Environment Variables on linux2
Please note that after the Oracle Cluster Ready Services (CRS) software is installed, you will need
to modify the CSS timeout value for CRS. This is especially true for 10.1.0.3 and 10.1.0.4
as the CSS timeout is computed differently than with 10.1.0.2. Several problems have been documented
as a result of the CSS daemon timing out starting with Oracle 10.1.0.3 on the Linux platform
(including IA32, IA64, and x86-64). This has been a big problem for me in the past, especially
during database creation (DBCA). During the database creation process, for example, it was not
uncommon for the database creation process to fail with the error: ORA-03113: end-of-file on communication channel.
The key error was reported in the log file $ORA_CRS_HOME/css/log/ocssd1.log as:
With 10.1.0.2, the timeout value was calculated as follows:
Starting with 10.1.0.3, the formula was changed to:
This change was motivated mainly in order to allow for a faster cluster reconfiguration
in case of node failure. With the default CSS misscount value of 60 in 10.1.0.2, we would have to
wait at least 60 seconds for a timeout, where this same default value of 60 can be shaved by 15 seconds to 45 seconds
starting with 10.1.0.3.
OK, so why all the talk about CSS misscount? As I mentioned earlier, I would often have the database
creation process fail (or other high I/O loads to the system) from the CRS crashing. The high I/O
would cause lengthy timeouts
for CSS while attempting to query the voting disk. When the calculated timeout was exceeded, CRS crashed.
This has been common with this article as the FireWire drives we are using are not the fastest.
The slower the drive, the more often this will occur.
Well, the good news is that we can modify the CSS misscount value from its default value of 60 (for Linux)
to allow for lengthier timeouts.
For the drives I have been using with this article, I have been able to get away with
a CSS misscount value of 180. Although I haven't been able to verify this, I believe the CSS misscount
can be set as large as 600.
So how do we modify the default value for CSS misscount? Well, there are several ways.
The easiest way is to modify the
root.sh for CRS
before running it on each node in the cluster. (The instructions for modifying the root.sh
script for CRS can be found here.)
If CRS is already installed, you can still modify the CSS misscount value using the $ORA_CRS_HOME/bin/crsctl
command. (The instructions for verifying and modifying the CSS misscount
using crsctl can be found in the section "Verifying Cluster Ready Services / CSS misscount value".)
The following tasks are used to install the Oracle Cluster Ready Services:
Navigate to the /u01/app/oracle/oraInventory directory
and run orainstRoot.sh.
Go back to the OUI and acknowledge the dialog window.
Navigate to the /u01/app/oracle/oraInventory directory
and run orainstRoot.sh ON ALL NODES
in the RAC cluster.
Go back to the OUI and acknowledge the dialog window.
For this installation, manually
create the file /u01/app/oracle/product/10.1.0/crs/log on
all nodes in the cluster.
The OUI will log all errors to a log file in this directory only if it
exists.
Click Install to start the installation!
Open a new console window on each node in the RAC cluster
as the "root" user account.
CLSCFG_MISCNT="-misscount 60"
to
CLSCFG_MISCNT="-misscount 180"
Now, run the root.sh file ON ALL NODES
in the RAC cluster ONE AT A TIME.
You will receive several warnings while running the root.sh script
on all nodes. These warnings can be safely ignored.
The root.sh may take awhile to run. When running the root.sh
on the last node, the output should look like:
Go back to the OUI and acknowledge the dialog window.
Check cluster nodes
Installing Oracle10g R1 Database Software
For more information, see
http://otn.oracle.com/tech/linux/asmlib/install.html#10gr1.
Like the CRS install (previous section),
the Oracle10g database software only needs to be run from one node. The OUI will
copy the software packages to all nodes configured in the RAC cluster.
Login as oracle
Unset ORACLE_HOME
Verify Environment Variables on linux1
Verify Environment Variables on linux2
Set the destination for the ORACLE_HOME name and location
as follows:
Remember that the OUI for 10g R1 (10.1) cannot discover
disks that were marked as Linux ASMLib. We will create the clustered database
as a separate step using dbca.
For this installation, manually
create the file /u01/app/oracle/product/10.1.0/db_1/log on
the node you are performing the installation from.
The OUI will log all errors to a log file in this directory only if it
exists.
Click Install to start the installation!
First, open a new console window
on the node you are installing the Oracle10g database
software from. For me, this was "linux1".
Navigate to the /u01/app/oracle/product/10.1.0/db_1 directory
and run root.sh.
At the end of the root.sh script,
it will bring up the GUI installer named "VIP Configuration Assistant".
The "VIP Configuration Assistant" will only come up on the first node you
run the root.sh from. You still, however, need to continue running the
root.sh script on all nodes in the cluster one at a time.
When the "VIP Configuration Assistant" appears, this is how I
answered the screen prompts:
Welcome: Click Next
Node Name: linux2
Summary: Click Finish
When running the root.sh
script on the remaining nodes, the end of the script will display "CRS resources are already configured".
Go back to the OUI and acknowledge the dialog window.
Creating TNS Listener Process
The process of creating the TNS listener only needs to be performed on
one of the nodes in the RAC cluster. All changes will be made and replicated to all
nodes in the cluster. On one of the nodes (I will be using linux1)
bring up the Network Configuration Assistant (NETCA) and run through the
process of creating a new TNS listener process and to also configure the node for
local access.
To start the NETCA, run the following GUI utility as the oracle user account:
The following screenshots walk you through the process of creating a new
Oracle listener for our RAC environment.
Creating the Oracle Cluster Database
Before executing the Database Configuration Assistant, make sure that
$ORACLE_HOME and $PATH are set appropriately for the
$ORACLE_BASE/product/10.1.0/db_1 environment.
You should also verify that all services we have installed up to this point
(Oracle TNS listener, CRS processes, etc.) are running
before attempting to start the clustered database creation process.
You will then be prompted with a dialog box asking if you want to create and start the
ASM instance. Select the OK button to acknowledge this dialog.
The OUI will now create and start the ASM instance on all nodes in the RAC cluster.
If the volumes we created earlier in this article do not show up in the
"Select Member Disks" window:
(ORCL:VOL1, ORCL:VOL2, and
ORCL:VOL3
then click on the "Change Disk Discovery Path" button and input "ORCL:VOL*".
For the "Disk Group Name", I used the string ORCL_DATA1.
Select all of the ASM volumes in the "Select Member Disks" window. All three volumes
should have a status of "PROVISIONED".
After verifying all values in this window are correct, click the OK button.
This will present the "ASM Disk Group Creation" dialog.
When the ASM Disk Group Creation process is finished, you will be returned to
the "ASM Disk Groups" windows. Select the checkbox next to the newly created
Disk Group Name ORCL_DATA1 and click [Next] to continue.
Click OK on the "Summary" screen.
When exiting the DBCA, another dialog will come up indicating that
it is starting all Oracle instances and HA service "orcltest". This
may take several minutes to complete. When finished, all windows and
dialog boxes will disappear.
When the Oracle Database Configuration Assistant has completed, you will
have a fully functional Oracle RAC cluster running!
Use the following to verify the orcltest service was
successfully added:
If the only service defined was for orcl.idevelopment.info, then
you will need to manually add the service to both instances:
Verifying TNS Networking Files
For clarity, I included a copy of the listener.ora file from my
node linux1:
You can include any of these entries on other client machines
that need access to the clustered database.
Then try to connect to the clustered database using all available service names defined
in the tnsnames.ora file:
Creating / Altering Tablespaces
This section provides several optional SQL commands I used to modify and
create all tablespaces for my testing database. Please keep in
mind that the database file names (OMF files) I used in this example may
differ from what Oracle creates for your environment.
Here is a snapshot of the tablespaces I have defined for my test database environment:
Verifying the RAC Cluster / Database Configuration
Starting & Stopping the Cluster
With all of the work we have done up to this point, a popular question
might be, "How do we start and stop services?". If you have followed
the instructions in this article, all services should start automatically
on each reboot of the Linux nodes. This would include CRS, all Oracle instances,
Enterprise Manager Database Console, etc.
There are times, however, when you might want to shutdown a node and manually
start it back up. Or you may find that Enterprise Manager is not running
and need to start it. This section provides the commands (using SRVCTL)
responsible for starting and stopping the cluster environment.
Ensure that you are logged in as the "oracle" UNIX user. I will
be running all of the commands in this section from linux1:
Transparent Application Failover - (TAF)
A major component of Oracle10g RAC that is responsible for failover processing
is the Transparent Application Failover (TAF) option. All database connections
(and processes) that loose connections are reconnected to another node within the
cluster. The failover is completely transparent to the user.
This final section provides a short demonstration on how automatic failover works in
Oracle10g RAC. Please note that a complete discussion on failover in Oracle10g
RAC would be an article in of its own. My intention here is to present a brief overview
and example of how it works.
One important note before continuing is that TAF happens automatically within the OCI
libraries. This means that your application (client) code does not need to change
in order to take advantage of TAF. Certain configuration steps, however, will need
to be done on the Oracle TNS file tnsnames.ora.
Setup tnsnames.ora File
During the creation of the clustered database in this article, I created a new service
that will be used for testing TAF named ORCLTEST. It provides all of
the necessary configuration parameters for load balancing
and failover. You can copy the contents of this entry to the
%ORACLE_HOME%\network\admin\tnsnames.ora file on the client machine
(my Windows laptop is being used in this example) in order to connect
to the new Oracle clustered database:
SQL Query to Check the Session's Failover Information
Transparent Application Failover Demonstration
Conclusion
This article has hopefully given you an economical solution to setting up
and configuring an inexpensive Oracle10g RAC Cluster using White Box Enterprise
Linux (or Red Hat Enterprise Linux 3) and FireWire technology. The RAC solution presented in this article can be
put together for around $1700 and will provide the DBA with a fully
functional Oracle10g RAC cluster. While this solution should be stable
enough for testing and development, it should never be considered for a
production environment.
Acknowledgements
First, I would like to thank Werner Puschitz for his outstanding work on
"Installing Oracle Database 10g with Real Application Cluster (RAC) on
Red Hat Enterprise Linux Advanced Server 3". This article,
along with several others of his, provided information on Oracle10g RAC that could not
be found in any other Oracle documentation. Without his hard work and research
into issues like configuring and installing the hangcheck-timer kernel module,
properly configuring UNIX shared memory, and configuring ASMLib,
this article may have never come to fruition. If you are interested in examining
technical articles on Linux internals and in-depth Oracle configurations written
by Werner Puschitz, please visit his excellent website at
www.puschitz.com.
I would next like to thank Wim Coekaerts, Manish Singh and the entire team at Oracle's Linux Projects Development
Group. The professionals in this group made the job of upgrading the Linux
kernel to support IEEE1394 devices with multiple logins (and several other
significant modifications) a seamless task. The group provides a pre-compiled
kernel for Red Hat Enterprise Linux 3.0 (which also works with White Box Enterprise Linux) along with
many other useful tools and documentation at
oss.oracle.com.
About the Author
Jeffrey Hunter is an Oracle Certified Professional, Java Development Certified Professional, Author,
and an Oracle ACE.
Jeff currently works as a Senior Database Administrator for
The DBA Zone, Inc. located in Pittsburgh, Pennsylvania.
His work includes advanced performance tuning, Java and PL/SQL programming, capacity
planning, database security, and physical / logical database design in a UNIX,
Linux, and Windows server environment. Jeff's other interests include mathematical
encryption theory, programming language processors (compilers and interpreters)
in Java and C, LDAP, writing web-based database administration tools, and of
course Linux. He has been a Sr. Database Administrator and Software Engineer
for over 16 years and maintains his own website site at:
http://www.iDevelopment.info.
Jeff graduated from Stanislaus State University in Turlock,
California, with a Bachelor's degree in Computer Science.
All articles, scripts and material located at the Internet address of http://www.idevelopment.info is the copyright of Jeffrey M. Hunter
and is protected under copyright laws of the United States. This document may not be hosted on any other site without my express,
prior, written permission. Application to host any of the material elsewhere can be made by contacting me at jhunter@idevelopment.info.
I have made every effort and taken great care in making sure that the material included on my web site is technically accurate,
but I disclaim any and all responsibility for any loss, damage or destruction of data or any other property which may arise from
relying on it. I will in no case be liable for any monetary damages arising from such loss, damage or destruction.
One of the most efficient ways to become familiar with Oracle10g Real
Application Cluster (RAC) technology is to have access to an actual
Oracle10g RAC cluster. In learning this new technology, you will soon start
to realize the benefits Oracle10g RAC has to offer like fault tolerance,
new levels of security, load balancing, and the ease of upgrading capacity. The problem though is the
price of the hardware required for a typical production RAC configuration.
A small two node cluster, for example, could run anywhere from $10,000
to well over $20,000. This would not even include the heart of a production
RAC environment, the shared storage. In most cases, this would be a Storage
Area Network (SAN), which generally start at $8,000.
If you are interested in configuring the same type of configuration
for Oracle9i, please see my article entitled
"Building an Inexpensive Oracle9i RAC Configuration on Linux".
This article is only designed to work as documented with absolutely no substitutions.
If you are looking for an example that takes advantage of 10g R2 with Red Hat 4,
please see
"Building an Inexpensive Oracle10g Release 2 RAC Configuration on Linux - (CentOS 4.2)".
Oracle Database Files
RAC Node Name
Instance Name
Database Name
$ORACLE_BASE
File System
linux1
orcl1
orcl
/u01/app/oracle
Automatic Storage Management (ASM)
linux2
orcl2
orcl
/u01/app/oracle
Automatic Storage Management (ASM)
Oracle CRS Shared Files
File Type
File Name
Partition
Mount Point
File System
Oracle Cluster Registry (OCR)
/u02/oradata/orcl/OCRFile
/dev/sda1
/u02/oradata/orcl
Oracle's Cluster File System (OCFS)
CRS Voting Disk
/u02/oradata/orcl/CSSFile
/dev/sda1
/u02/oradata/orcl
Oracle's Cluster File System (OCFS)
The Oracle database files could have just as well been stored on
the Oracle Cluster File System (OFCS). Using ASM, however, makes
the article that much more interesting!
Oracle Real Application Cluster (RAC) is the successor to Oracle
Parallel Server (OPS) and was first introduced in Oracle9i. RAC allows multiple instances to access the same
database (storage) simultaneously. RAC provides fault tolerance, load balancing, and
performance benefits by allowing the system to scale out, and at the same
time since all nodes access the same database, the failure of one instance
will not cause the loss of access to the database.
Today, fibre channel is one of the most popular solutions for shared storage.
As mentioned earlier, fibre channel is a high-speed serial-transfer interface
that is used to connect systems and storage devices in either point-to-point
or switched topologies. Protocols supported by Fibre Channel include SCSI
and IP. Fibre channel configurations can support as many as 127 nodes
and have a throughput of up to 2.12 gigabits per second. Fibre channel, although, is
very expensive. Just the fibre channel switch alone can run as much as $1000. This
does not even include the fibre channel storage array and high-end drives,
which can reach prices of about $300 for a 36GB drive. A typical fibre channel setup
which includes fibre channel cards for the servers, a basic setup is roughly $5,000,
which does not include the cost of the servers that make up the cluster.
Developed by Apple Computer and Texas Instruments, FireWire is a cross-platform
implementation of a high-speed serial data bus. With its high bandwidth, long
distances (up to 100 meters in length) and high-powered bus, FireWire is being
used in applications such as
digital video (DV), professional audio, hard drives, high-end digital still cameras
and home entertainment devices. Today, FireWire operates at transfer rates of up to
800 megabits per second while next generation FireWire calls for speeds to a theoretical
bit rate to 1600 Mbps and then up to a staggering 3200 Mbps. That's 3.2 gigabits per
second. This will make FireWire indispensable for transferring massive data files
and for even the most demanding video applications, such as working
with uncompressed high-definition (HD) video or multiple standard-definition (SD)
video streams.
Disk Interface / Network / BUS
Speed
Kb
KB
Mb
MB
Gb
GB
Serial
115
14.375
0.115
0.014
Parallel (standard)
920
115
0.92
0.115
10Base-T Ethernet
10
1.25
IEEE 802.11b wireless Wi-Fi (2.4 GHz band)
11
1.375
USB 1.1
12
1.5
Parallel (ECP/EPP)
24
3
SCSI-1
40
5
IEEE 802.11g wireless WLAN (2.4 GHz band)
54
6.75
SCSI-2 (Fast SCSI / Fast Narrow SCSI)
80
10
100Base-T Ethernet (Fast Ethernet)
100
12.5
ATA/100 (parallel)
100
12.5
IDE
133.6
16.7
Fast Wide SCSI (Wide SCSI)
160
20
Ultra SCSI (SCSI-3 / Fast-20 / Ultra Narrow)
160
20
Ultra IDE
264
33
Wide Ultra SCSI (Fast Wide 20)
320
40
Ultra2 SCSI
320
40
FireWire 400 - (IEEE1394a)
400
50
USB 2.0
480
60
Wide Ultra2 SCSI
640
80
Ultra3 SCSI
640
80
FireWire 800 - (IEEE1394b)
800
100
Gigabit Ethernet
1000
125
1
PCI - (33 MHz / 32-bit)
1064
133
1.064
Serial ATA I - (SATA I)
1200
150
1.2
Wide Ultra3 SCSI
1280
160
1.28
Ultra160 SCSI
1280
160
1.28
PCI - (33 MHz / 64-bit)
2128
266
2.128
PCI - (66 MHz / 32-bit)
2128
266
2.128
AGP 1x - (66 MHz / 32-bit)
2128
266
2.128
Serial ATA II - (SATA II)
2400
300
2.4
Ultra320 SCSI
2560
320
2.56
FC-AL Fibre Channel
3200
400
3.2
PCI-Express x1 - (bidirectional)
4000
500
4
PCI - (66 MHz / 64-bit)
4256
532
4.256
AGP 2x - (133 MHz / 32-bit)
4264
533
4.264
Serial ATA III - (SATA III)
4800
600
4.8
PCI-X - (100 MHz / 64-bit)
6400
800
6.4
PCI-X - (133 MHz / 64-bit)
1064
8.512
1
AGP 4x - (266 MHz / 32-bit)
1066
8.528
1
10G Ethernet - (IEEE 802.3ae)
1250
10
1.25
PCI-Express x4 - (bidirectional)
2000
16
2
AGP 8x - (533 MHz / 32-bit)
2133
17.064
2.1
PCI-Express x8 - (bidirectional)
4000
32
4
PCI-Express x16 - (bidirectional)
8000
64
8
The hardware used to build our example Oracle10g RAC environment
consists of two Linux servers and components
that can be purchased at any local computer store or over the Internet.
Server 1 - (linux1)
Dimension 2400 Series
- Intel Pentium 4 Processor at 2.80GHz
- 1GB DDR SDRAM (at 333MHz)
- 40GB 7200 RPM Internal Hard Drive
- Integrated Intel 3D AGP Graphics
- Integrated 10/100 Ethernet - (Broadcom BCM4401)
- CDROM (48X Max Variable)
- 3.5" Floppy
- No monitor (Already had one)
- USB Mouse and Keyboard
$620
1 - Ethernet LAN Cards
Linksys 10/100 Mpbs - (LNE100TX) - (Used for Interconnect to linux2)
$20
1 - FireWire Card
Belkin FireWire 3-Port 1394 PCI Card - (F5U501-APL)
SIIG 3-Port 1394 I/O Card - (NN-300012)
StarTech 4 Port IEEE-1394 PCI Firewire Card - (PCI1394_4)
Adaptec FireConnect 4300 FireWire PCI Card - (1890600)
$30
Server 2 - (linux2)
Dimension 2400 Series
- Intel Pentium 4 Processor at 2.80GHz
- 1GB DDR SDRAM (at 333MHz)
- 40GB 7200 RPM Internal Hard Drive
- Integrated Intel 3D AGP Graphics
- Integrated 10/100 Ethernet - (Broadcom BCM4401)
- CDROM (48X Max Variable)
- 3.5" Floppy
- No monitor (Already had one)
- USB Mouse and Keyboard
$620
1 - Ethernet LAN Cards
Linksys 10/100 Mpbs - (LNE100TX) - (Used for Interconnect to linux1)
$20
1 - FireWire Card
Belkin FireWire 3-Port 1394 PCI Card - (F5U501-APL)
SIIG 3-Port 1394 I/O Card - (NN-300012)
StarTech 4 Port IEEE-1394 PCI Firewire Card - (PCI1394_4)
Adaptec FireConnect 4300 FireWire PCI Card - (1890600)
$30
Miscellaneous Components
FireWire Hard Drive
Maxtor OneTouch III - 750GB FireWire 400/USB 2.0 Drive - (T01G750)
Maxtor OneTouch III - 500GB FireWire 400/USB 2.0 Drive - (T01G500)
Maxtor OneTouch III - 300GB FireWire 400/USB 2.0 Drive - (T01G300)
Maxtor OneTouch III - 500GB FireWire 400/USB 2.0 Drive - (F01G500)
Maxtor OneTouch III - 300GB FireWire 400/USB 2.0 Drive - (F01G300)
Maxtor OneTouch II 300GB USB 2.0 / IEEE 1394a External Hard Drive - (E01G300)
Maxtor OneTouch II 250GB USB 2.0 / IEEE 1394a External Hard Drive - (E01G250)
Maxtor OneTouch II 200GB USB 2.0 / IEEE 1394a External Hard Drive - (E01A200)
LaCie Hard Drive, Design by F.A. Porsche 250GB, FireWire 400 - (300703U)
LaCie Hard Drive, Design by F.A. Porsche 160GB, FireWire 400 - (300702U)
LaCie Hard Drive, Design by F.A. Porsche 80GB, FireWire 400 - (300699U)
Dual Link Drive Kit, FireWire Enclosure, ADS Technologies - (DLX185)
Maxtor Ultra 200GB ATA-133 (Internal) Hard Drive - (L01P200)
Maxtor OneTouch 250GB USB 2.0 / IEEE 1394a External Hard Drive - (A01A250)
Maxtor OneTouch 200GB USB 2.0 / IEEE 1394a External Hard Drive - (A01A200)
Ensure that the FireWire drive that you purchase supports multiple logins. If the drive
has a chipset that does not allow for concurrent access for more than one server,
the disk and its partitions can only be seen by one server at a time. Disks with
the Oxford 911 chipset are known to work. Here are the
details about the disk that I purchased for this test:
Vendor: Maxtor
Model: OneTouch II
Mfg. Part No. or KIT No.: E01G300
Capacity: 300 GB
Cache Buffer: 16 MB
Rotational Speed (rpm): 7200 RPM
Interface Transfer Rate : 400 Mbits/s
"Combo" Interface: IEEE 1394 / USB 2.0 and USB 1.1 compatible
$280
1 - Extra FireWire Cable
Belkin 6-pin to 6-pin 1394 Cable, 3 ft. - (F3N400-03-ICE)
Belkin 6-pin to 6-pin 1394 Cable, 14 ft. - (F3N400-14-ICE)
$20
1 - Ethernet hub or switch
Linksys EtherFast 10/100 5-port Ethernet Switch - (EZXS55W)
$25
4 - Network Cables
Category 5e patch cable - (Connect linux1 to public network)
Category 5e patch cable - (Connect linux2 to public network)
Category 5e patch cable - (Connect linux1 to interconnect ethernet switch)
Category 5e patch cable - (Connect linux2 to interconnect ethernet switch)
$5
$5
$5
$5
Total
$1685
I have received several emails since posting this article asking if the
Maxtor OneTouch external drive (and the other external hard drives I have listed) has
two IEEE1394 (FireWire) ports. All of the drives that I have listed and
tested do have two IEEE1394 ports located on the back of the drive.
We are about to start the installation process. Now that we have
talked about the hardware that will be used in this example, let's
take a conceptual look at what the environment would look:
Perform the following installation on all nodes in the cluster!
After procuring the required hardware, it is time to start the configuration
process. The first task we need to perform is to install the
Linux operating system. As already mentioned,
this article will use White Box Enterprise Linux (WBEL) 3.0.
Although I have used Red Hat Fedora in the past, I wanted to switch
to a Linux environment that would guarantee all of the functionality
contained with Oracle. This is where WBEL comes in.
The WBEL Linux project takes the Red Hat Enterprise Linux 3 source RPMs, and compiles
them into a free clone of the Enterprise Server 3.0 product. This provides
a free and stable version of the Red Hat Enterprise Linux 3 (AS/ES) operating environment for
testing different Oracle configurations. Over the last several months, I have been
moving away from Fedora as I need a stable environment that is not only
free, but as close to the actual Oracle supported operating system as possible.
While WBEL is not the only project performing the same functionality, I
tend to stick with it as it is stable and has been around the longest.
Downloading White Box Enterprise Linux
Use the links (below) to download White Box Enterprise Linux 3.0. After
downloading WBEL, you will then want to burn each of the ISO images
to CD.
If you are downloading the above ISO files to a MS Windows machine,
there are many options for burning these images (ISO files) to a CD. You
may already be familiar with and have the proper software
to burn images to CD. If you are not familiar with this process
and do not have the required software to burn images to CD, here are just
two (of many) software packages that can be used:
Installing White Box Enterprise Linux
This section provides a summary of the screens used to install
White Box Enterprise Linux. For more detailed installation instructions, it
is possible to use the manuals from Red Hat Linux
http://www.redhat.com/docs/manuals/.
I would suggest, however, that the instructions I have provided
below be used for this Oracle10g RAC configuration.
Before installing the Linux operating system on both
nodes, you should have
the FireWire and two NIC interfaces (cards) installed.
The first screen is the White Box Enterprise Linux boot screen.
At the boot: prompt, hit [Enter] to start the installation process.
Media Test
When asked to test the CD media, tab over to [Skip] and hit
[Enter]. If there
were any errors, the media burning software would have warned us. After several
seconds, the installer should then detect the video card, monitor, and mouse.
The installer then goes into GUI mode.
Welcome to White Box Enterprise Linux
At the welcome screen, click [Next] to continue.
Language / Keyboard / Mouse Selection
The next three screens prompt you for the Language, Keyboard, and Mouse
settings. Make the appropriate selections for your configuration.
Installation Type
Choose the [Custom] option and click [Next] to continue.
Disk Partitioning Setup
Select [Automatically partition] and click [Next] continue.
Partitioning
The installer will then allow you to view (and modify if needed)
the disk partitions it automatically selected. In most cases, the
installer will choose 100MB for /boot, double the amount of
RAM for swap, and the rest going to the root (/) partition. I like to
have a minimum of 1GB for swap. For the purpose of this install,
I will accept all automatically preferred sizes. (Including
2GB for swap since I have 1GB of RAM installed.)
Boot Loader Configuration
The installer will use the GRUB boot loader by default.
To use the GRUB boot loader, accept all default values and click [Next] to continue.
Network Configuration
I made sure to install both NIC interfaces (cards) in each of the
Linux machines before starting the operating system installation.
This screen should have successfully detected each of the network
devices.
Firewall
- Check OFF the option to [Configure using DHCP]
- Leave the [Activate on boot] checked ON
- IP Address: 192.168.1.100
- Netmask: 255.255.255.0
- Check OFF the option to [Configure using DHCP]
- Leave the [Activate on boot] checked ON
- IP Address: 192.168.2.100
- Netmask: 255.255.255.0
On this screen, make sure to check [No firewall]
and click [Next] to continue.
Additional Language Support / Time Zone
The next two screens allow you to select additional language support
and time zone information.
In almost all cases, you can accept the defaults.
Set Root Password
Select a root password and click [Next] to continue.
Package Group Selection
Scroll down to the bottom of this screen and select
[Everything] under the Miscellaneous section. Click
[Next] to continue.
About to Install
This screen is basically a confirmation screen. Click [Next]
to start the installation. During the installation process,
you will be asked to switch disks to Disk #2 and then Disk #3.
Graphical Interface (X) Configuration
When the installation is complete, the installer will attempt to detect
your video hardware. Ensure that the installer has detected
and selected the correct video hardware (graphics card and monitor) to
properly use the X Windows server. You will continue with the X
configuration in the next three screens.
Congratulations
And that's it. You have successfully installed White Box Enterprise Linux
on the first node (linux1). The installer will eject the CD
from the CD-ROM drive. Take out the CD and click [Exit] to reboot
the system.
Perform the same installation on the second node
After completing the Linux installation on the first node, repeat the above
steps for the second node (linux2). When configuring the machine name
and networking, ensure to configure the proper values. For my installation,
this is what I configured for linux2:
- Check off the option to [Configure using DHCP]
- Leave the [Activate on boot] checked
- IP Address: 192.168.1.101
- Netmask: 255.255.255.0
- Check off the option to [Configure using DHCP]
- Leave the [Activate on boot] checked
- IP Address: 192.168.2.101
- Netmask: 255.255.255.0
Perform the following network configuration on all nodes in the cluster!
Although we configured several of the network
settings during the installation of White Box Enterprise Linux, it is important
to not skip this section as it contains critical
steps that are required for a successful RAC environment.
Introduction to Network Settings
During the Linux O/S install we already configured the IP address and
host name for each of the nodes.
We now need to configure
the /etc/hosts file as well as adjusting several of the
network settings for the interconnect.
Configuring Public and Private Network
In our two node example, we need to configure the network on both nodes
for access to the public network as well as their private interconnect.
# su -
# /usr/bin/redhat-config-network &
Do not use DHCP naming for the public IP address or the interconnects - we need static IP addresses!
/etc/hosts file. Both of these tasks can
be completed using the Network Configuration GUI. Notice that the /etc/hosts
entries are the same for both nodes.
Server 1 - (linux1)
Device
IP Address
Subnet
Gateway
Purpose
eth0
192.168.1.100
255.255.255.0
192.168.1.1
Connects linux1 to the public network
eth1
192.168.2.100
255.255.255.0
Connects linux1 (interconnect) to linux2 (int-linux2)
/etc/hosts
127.0.0.1 localhost loopback
# Public Network - (eth0)
192.168.1.100 linux1
192.168.1.101 linux2
# Private Interconnect - (eth1)
192.168.2.100 int-linux1
192.168.2.101 int-linux2
# Public Virtual IP (VIP) addresses for - (eth0)
192.168.1.200 vip-linux1
192.168.1.201 vip-linux2
Server 2 - (linux2)
Device
IP Address
Subnet
Gateway
Purpose
eth0
192.168.1.101
255.255.255.0
192.168.1.1
Connects linux2 to the public network
eth1
192.168.2.101
255.255.255.0
Connects linux2 (interconnect) to linux1 (int-linux1)
/etc/hosts
127.0.0.1 localhost loopback
# Public Network - (eth0)
192.168.1.100 linux1
192.168.1.101 linux2
# Private Interconnect - (eth1)
192.168.2.100 int-linux1
192.168.2.101 int-linux2
# Public Virtual IP (VIP) addresses for - (eth0)
192.168.1.200 vip-linux1
192.168.1.201 vip-linux2
Note that the virtual IP addresses only need to be defined in the /etc/hosts file for both
nodes. The public virtual IP addresses will be configured automatically by Oracle when you run the
Oracle Universal Installer, which starts Oracle's Virtual Internet Protocol Configuration Assistant (VIPCA).
All virtual IP addresses will be activated when the srvctl start nodeapps -n <node_name> command
is run. Although I am getting ahead of myself, this is the Host Name/IP Address that will be
configured in the client(s) tnsnames.ora file for each Oracle Net Service Name.
All of this will be explained much later in this article!
In the screen shots below, only node 1 (linux1) is shown. Ensure to make
all the proper network settings to both nodes!
Network Configuration Screen - Node 1 (linux1)
Ethernet Device Screen - eth0 (linux1)
Ethernet Device Screen - eth1 (linux1)
Network Configuration Screen - /etc/hosts (linux1)
Once the network if configured, you can use the ifconfig
command to verify everything is working. The following example
is from linux1:
$ /sbin/ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:0C:41:F1:6E:9A
inet addr:192.168.1.100 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:421591 errors:0 dropped:0 overruns:0 frame:0
TX packets:403861 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:78398254 (74.7 Mb) TX bytes:51064273 (48.6 Mb)
Interrupt:9 Base address:0x400
eth1 Link encap:Ethernet HWaddr 00:0D:56:FC:39:EC
inet addr:192.168.2.100 Bcast:192.168.2.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1715352 errors:0 dropped:1 overruns:0 frame:0
TX packets:4257279 errors:0 dropped:0 overruns:0 carrier:4
collisions:0 txqueuelen:1000
RX bytes:802574993 (765.3 Mb) TX bytes:1236087657 (1178.8 Mb)
Interrupt:3
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:1273787 errors:0 dropped:0 overruns:0 frame:0
TX packets:1273787 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:246580081 (235.1 Mb) TX bytes:246580081 (235.1 Mb)
About Virtual IP
Why do we have a Virtual IP (VIP) in 10g?
Why does it just return a dead connection when its primary node fails?
Make sure RAC node name is not listed in loopback address
Ensure that none of the node names (linux1 or linux2) are
included for the loopback address in the /etc/hosts file.
If the machine name is listed in the in the loopback address entry as below:
127.0.0.1 linux1 localhost.localdomain localhost
it will need to be removed as shown below:
127.0.0.1 localhost.localdomain localhost
If the RAC node name is listed for the loopback address, you will
receive the following error during the RAC installation:
ORA-00603: ORACLE server session terminated by fatal error
or
ORA-29702: error occurred in Cluster Group Service operation
Adjusting Network Settings
With Oracle 9.2.0.1 and onwards, Oracle now makes use of UDP as the default protocol
on Linux for inter-process communication (IPC), such as Cache Fusion
and Cluster Manager buffer transfers
between instances within the RAC cluster.
The default and maximum window size can be changed in the /proc file system
without reboot:
# su - root
# sysctl -w net.core.rmem_default=262144
net.core.rmem_default = 262144
# sysctl -w net.core.wmem_default=262144
net.core.wmem_default = 262144
# sysctl -w net.core.rmem_max=262144
net.core.rmem_max = 262144
# sysctl -w net.core.wmem_max=262144
net.core.wmem_max = 262144
# Default setting in bytes of the socket receive buffer
net.core.rmem_default=262144
# Default setting in bytes of the socket send buffer
net.core.wmem_default=262144
# Maximum socket receive buffer size which may be set by using
# the SO_RCVBUF socket option
net.core.rmem_max=262144
# Maximum socket send buffer size which may be set by using
# the SO_SNDBUF socket option
net.core.wmem_max=262144
Check and turn off UDP ICMP rejections:
During the Linux installation process, I indicated to not configure the
firewall option. (By default the option to configure a firewall is selected
by the installer.)
This has burned me several times so I like to do a double-check that the firewall
option is not configured and to ensure udp ICMP filtering is turned off.
08/29/2005 22:17:19
oac_init:2: Could not connect to server, clsc retcode = 9
08/29/2005 22:17:19
a_init:12!: Client init unsuccessful : [32]
ibctx:1:ERROR: INVALID FORMAT
proprinit:problem reading the bootblock or superbloc 22
When experiencing this type of error, the solution was to remove the udp ICMP (iptables)
rejection rule - or to simply have the firewall option turned off.
The CRS will then start to operate normally and not crash. The following commands
should be executed as the root user account:
# /etc/rc.d/init.d/iptables status
Firewall is stopped.
# /etc/rc.d/init.d/iptables stop
Flushing firewall rules: [ OK ]
Setting chains to policy ACCEPT: filter [ OK ]
Unloading iptables modules: [ OK ]
# chkconfig iptables off
Perform the following kernel upgrade on all nodes in the cluster!
Overview
The next step is to obtain and install a new Linux kernel that supports the use
of IEEE1394 devices with multiple logins. In previous releases of this article,
I included the steps to download a patched version of the Linux kernel (source code) and then
compile it. Thanks to
Oracle's Linux Projects development group, this
is no longer a requirement. They provide a pre-compiled kernel for Red Hat Enterprise Linux 3.0
(which also works with White Box Enterprise Linux!), that can simply be
downloaded and installed. The instructions for downloading and installing the kernel
are included in this section. Before going into the details of how to perform these actions,
however, lets take a moment to discuss the changes that are required in the new kernel.
I am using the term "multiple logins" a bit loosely in this article. The concept of "multiple login"
is strictly not allowed in the IEEE1394 specification, as it is only a point to point protocol.
The term "multiple logins", is often confused with "concurrent sessions", which is supported in the
IEEE1394 specification. It simply means that the device allows multiple outstanding requests
simultaneously (similar to the SCSI-2 protocol). Therefore multiple hosts (initiators) on a single
bus are prohibited according to IEEE1394.
Download one of the following files:
- OR -
Take a backup of your GRUB configuration file:
In most cases you will be using GRUB for the boot loader. Before actually installing the new kernel,
backup a copy of your /etc/grub.conf file:
# cp /etc/grub.conf /etc/grub.conf.original
Install the new kernel, as root:
# rpm -ivh --force kernel-2.4.21-27.0.2.ELorafw1.i686.rpm - (for single processor)
- OR -
# rpm -ivh --force kernel-smp-2.4.21-27.0.2.ELorafw1.i686.rpm - (for multiple processors)
Installing the new kernel using RPM will also update your GRUB (or lilo)
configuration with the appropiate stanza. There is no need to add any new
stanza to your boot loader configuration unless you want to have
your old kernel image available.
Original /etc/grub.conf File # grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/hda2
# initrd /initrd-version.img
#boot=/dev/hda
default=0
timeout=10
splashimage=(hd0,0)/grub/splash.xpm.gz
title White Box Enterprise Linux (2.4.21-15.EL)
root (hd0,0)
kernel /vmlinuz-2.4.21-15.EL ro root=LABEL=/
initrd /initrd-2.4.21-15.EL.img
Newly Configured /etc/grub.conf File After Kernel Install # grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/hda2
# initrd /initrd-version.img
#boot=/dev/hda
default=0
timeout=10
splashimage=(hd0,0)/grub/splash.xpm.gz
title White Box Enterprise Linux (2.4.21-27.0.2.ELorafw1)
root (hd0,0)
kernel /vmlinuz-2.4.21-27.0.2.ELorafw1 ro root=LABEL=/
initrd /initrd-2.4.21-27.0.2.ELorafw1.img
title White Box Enterprise Linux (2.4.21-15.EL)
root (hd0,0)
kernel /vmlinuz-2.4.21-15.EL ro root=LABEL=/
initrd /initrd-2.4.21-15.EL.img
Add module options:
Add the following lines to /etc/modules.conf:
alias ieee1394-controller ohci1394
options sbp2 sbp2_exclusive_login=0
post-install sbp2 insmod sd_mod
post-install sbp2 insmod ohci1394
post-remove sbp2 rmmod sd_mod
Connect FireWire drive to each machine and boot into the new kernel:
After you have performed the above tasks on both nodes in the cluster,
power down both of them:
===============================
# hostname
linux1
# init 0
===============================
# hostname
linux2
# init 0
===============================
After both machines are powered down, connect each of them to the back of the FireWire drive.
Check and turn off UDP ICMP rejections:
After rebooting each machine (above)
check to ensure that the firewall option is turned off (stopped):
# /etc/rc.d/init.d/iptables status
Firewall is stopped.
Loading the FireWire stack:
Starting with Red Hat Enterprise Linux (and of course White Box Enterprise Linux!),
the loading of the FireWire stack should already be configured!
# modprobe sbp2
# modprobe ohci1394
In older versions of Red Hat, this was not the case and these commands
would have to be manually run or put within a startup file. With Red Hat Enterprise Linux
and higher, these commands are already put within the /etc/rc.sysinit file
and run on each boot.
Check for SCSI Device:
After each machine has rebooted, the kernel should automatically detect
the shared disk as a SCSI device (/dev/sdXX). This section will provide
several commands that should be run on all nodes in the cluster to
verify the FireWire drive was successfully detected and being shared by
all nodes in the cluster.
# lspci
00:00.0 Host bridge: Intel Corp. 82845G/GL[Brookdale-G]/GE/PE DRAM Controller/Host-Hub Interface (rev 01)
00:02.0 VGA compatible controller: Intel Corp. 82845G/GL[Brookdale-G]/GE Chipset Integrated Graphics Device (rev 01)
00:1d.0 USB Controller: Intel Corp. 82801DB (ICH4) USB UHCI #1 (rev 01)
00:1d.1 USB Controller: Intel Corp. 82801DB (ICH4) USB UHCI #2 (rev 01)
00:1d.2 USB Controller: Intel Corp. 82801DB (ICH4) USB UHCI #3 (rev 01)
00:1d.7 USB Controller: Intel Corp. 82801DB (ICH4) USB2 EHCI Controller (rev 01)
00:1e.0 PCI bridge: Intel Corp. 82801BA/CA/DB/EB/ER Hub interface to PCI Bridge (rev 81)
00:1f.0 ISA bridge: Intel Corp. 82801DB (ICH4) LPC Bridge (rev 01)
00:1f.1 IDE interface: Intel Corp. 82801DB (ICH4) Ultra ATA 100 Storage Controller (rev 01)
00:1f.3 SMBus: Intel Corp. 82801DB/DBM (ICH4) SMBus Controller (rev 01)
00:1f.5 Multimedia audio controller: Intel Corp. 82801DB (ICH4) AC'97 Audio Controller (rev 01)
01:04.0 FireWire (IEEE 1394): Texas Instruments TSB43AB23 IEEE-1394a-2000 Controller (PHY/Link)
01:05.0 Modem: Intel Corp.: Unknown device 1080 (rev 04)
01:06.0 Ethernet controller: Linksys NC100 Network Everywhere Fast Ethernet 10/100 (rev 11)
01:09.0 Ethernet controller: Broadcom Corporation BCM4401 100Base-T (rev 01)
Second, let's check to see that the modules are loaded:
# lsmod |egrep "ohci1394|sbp2|ieee1394|sd_mod|scsi_mod"
sd_mod 13808 0
sbp2 19724 0
scsi_mod 106664 3 [sg sd_mod sbp2]
ohci1394 28008 0 (unused)
ieee1394 62916 0 [sbp2 ohci1394]
Third, let's make sure the disk was detected and an entry was made by the kernel:
# cat /proc/scsi/scsi
Attached devices:
Host: scsi0 Channel: 00 Id: 00 Lun: 00
Vendor: Maxtor Model: OneTouch Rev: 0200
Type: Direct-Access ANSI SCSI revision: 06
Now let's verify that the FireWire drive is accessible for multiple logins and
shows a valid login:
# dmesg | grep sbp2
ieee1394: sbp2: Query logins to SBP-2 device successful
ieee1394: sbp2: Maximum concurrent logins supported: 3
ieee1394: sbp2: Number of active logins: 1
ieee1394: sbp2: Logged into SBP-2 device
ieee1394: sbp2: Node[01:1023]: Max speed [S400] - Max payload [2048]
# fdisk -l
Disk /dev/sda: 203.9 GB, 203927060480 bytes
255 heads, 63 sectors/track, 24792 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sda1 1 24791 199133676 c Win95 FAT32 (LBA)
Disk /dev/hda: 40.0 GB, 40000000000 bytes
255 heads, 63 sectors/track, 4863 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/hda1 * 1 13 104391 83 Linux
/dev/hda2 14 4609 36917370 83 Linux
/dev/hda3 4610 4863 2040255 82 Linux swap
Rescan SCSI bus no longer required:
With Red Hat Enterprise Linux 3 (and you guessed it, White Box Enterprise Linux),
you no longer need to rescan the SCSI bus in order
to detect the disk! The disk should be detected automatically by
the kernel as seen from the tests you performed above.
echo "scsi add-single-device 0 0 0 0" > /proc/scsi/scsi
Troubleshooting SCSI Device Detection:
If you are having troubles with any of the procedures (above) in detecting
the SCSI device, you can try the following:
# modprobe -r sbp2
# modprobe -r sd_mod
# modprobe -r ohci1394
# modprobe ohci1394
# modprobe sd_mod
# modprobe sbp2
Perform the following procedures on all nodes in the cluster!
I will be using the Oracle Cluster File System (OCFS) to store the files required to be shared
for the Oracle Cluster Ready Services (CRS).
When using OCFS, the UID of the UNIX user "oracle" and GID of the UNIX group "dba" must be the same
on all machines in the cluster. If either the UID or GID are different, the files on the OCFS file system
will show up as "unowned" or may even be owned by a different user. For this article, I will use
175 for the "oracle" UID and 115 for the "dba" GID.
Create Group and User for Oracle
Lets continue this example by creating the UNIX
dba group
and oracle user account along with all appropriate directories.
# mkdir -p /u01/app
# groupadd -g 115 dba
# useradd -u 175 -g 115 -d /u01/app/oracle -s /bin/bash -c "Oracle Software Owner" -p oracle oracle
# chown -R oracle:dba /u01
# passwd oracle
# su - oracle
When you are setting the Oracle environment variables for each RAC node, ensure to
assign each RAC node a unique Oracle SID!
The Oracle Universal Installer (OUI) requires at most 400MB of free space
in the /tmp directory.
# df -k /tmp
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/hda2 36337384 4691460 29800056 14% /
If for any reason, you do not have enough space in /tmp, you
can temporarily create space in another file system and point your
TEMP and TMPDIR to it for the duration of the install.
Here are the steps to do this:
# su -
# mkdir /<AnotherFilesystem>/tmp
# chown root.root /<AnotherFilesystem>/tmp
# chmod 1777 /<AnotherFilesystem>/tmp
# export TEMP=/<AnotherFilesystem>/tmp # used by Oracle
# export TMPDIR=/<AnotherFilesystem>/tmp # used by Linux programs
# like the linker "ld"
When the installation of Oracle is complete, you can remove the temporary directory using the following:
# su -
# rmdir /<AnotherFilesystem>/tmp
# unset TEMP
# unset TMPDIR
Create Login Script for oracle User Account
After creating the "oracle" UNIX user account on both nodes, make sure
that you are logged in as the oracle user and
verify that the environment is setup correctly by using the
following
.bash_profile:
.bash_profile for Oracle User # .bash_profile
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
. ~/.bashrc
fi
alias ls="ls -FA"
alias s="screen -DRRS iPad -t iPad"
# User specific environment and startup programs
export ORACLE_BASE=/u01/app/oracle
export ORACLE_HOME=$ORACLE_BASE/product/10.1.0/db_1
export ORA_CRS_HOME=$ORACLE_BASE/product/10.1.0/crs
export ORACLE_PATH=$ORACLE_BASE/common/oracle/sql:.:$ORACLE_HOME/rdbms/admin
# Each RAC node must have a unique ORACLE_SID. (i.e. orcl1, orcl2,...)
export ORACLE_SID=orcl1
export PATH=.:${PATH}:$HOME/bin:$ORACLE_HOME/bin
export PATH=${PATH}:/usr/bin:/bin:/usr/bin/X11:/usr/local/bin
export PATH=${PATH}:$ORACLE_BASE/common/oracle/bin
export ORACLE_TERM=xterm
export TNS_ADMIN=$ORACLE_HOME/network/admin
export ORA_NLS10=$ORACLE_HOME/nls/data
export NLS_DATE_FORMAT="DD-MON-YYYY HH24:MI:SS"
export LD_LIBRARY_PATH=$ORACLE_HOME/lib
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:$ORACLE_HOME/oracm/lib
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:/lib:/usr/lib:/usr/local/lib
export CLASSPATH=$ORACLE_HOME/JRE
export CLASSPATH=${CLASSPATH}:$ORACLE_HOME/jlib
export CLASSPATH=${CLASSPATH}:$ORACLE_HOME/rdbms/jlib
export CLASSPATH=${CLASSPATH}:$ORACLE_HOME/network/jlib
export THREADS_FLAG=native
export TEMP=/tmp
export TMPDIR=/tmp
export LD_ASSUME_KERNEL=2.4.1
Create the following partitions on only one node in the cluster!
Overview
The next step is to create the required partitions on the FireWire (shared) drive. As mentioned
earlier in this article, I will be using Oracle's Cluster File System (OCFS) to
store the two files to be shared for Oracle's Cluster Ready Service (CRS). I will then be
using Automatic Storage Management (ASM) for all physical database files (data/index files,
online redo log files, control files, SPFILE, and archived redo log files).
Oracle Shared Drive Configuration
File System Type
Partition
Size
Mount Point
File Types
OCFS
/dev/sda1
300 MB
/u02/oradata/orcl
Oracle Cluster Registry (OCR) File - (~100 MB)
CRS Voting Disk - (~20MB)
ASM
/dev/sda2
50 GB
ORCL:VOL1
Oracle Database Files
ASM
/dev/sda3
50 GB
ORCL:VOL2
Oracle Database Files
ASM
/dev/sda4
50 GB
ORCL:VOL3
Oracle Database Files
Total
150.3 GB
Like shown in the table (above) my FireWire drive shows up as the SCSI device
/dev/sda. The fdisk command is used for creating (and removing) partitions.
For this configuration, I will be creating four partitions - one for CRS and the other
three for ASM (to store all Oracle database files). Before creating the new partitions, it is
important to remove any existing partitions (if they exist) on the FireWire drive:
# fdisk /dev/sda
Command (m for help): p
Disk /dev/sda: 203.9 GB, 203927060480 bytes
255 heads, 63 sectors/track, 24792 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sda1 1 24791 199133676 c Win95 FAT32 (LBA)
Command (m for help): d
Selected partition 1
Command (m for help): p
Disk /dev/sda: 203.9 GB, 203927060480 bytes
255 heads, 63 sectors/track, 24792 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-24792, default 1): 1
Last cylinder or +size or +sizeM or +sizeK (1-24792, default 24792): +300M
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 2
First cylinder (38-24792, default 38): 38
Using default value 38
Last cylinder or +size or +sizeM or +sizeK (38-24792, default 24792): +50G
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 3
First cylinder (6118-24792, default 6118): 6118
Using default value 6118
Last cylinder or +size or +sizeM or +sizeK (6118-24792, default 24792): +50G
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Selected partition 4
First cylinder (12198-24792, default 12198): 12198
Using default value 12198
Last cylinder or +size or +sizeM or +sizeK (12198-24792, default 24792): +50G
Command (m for help): p
Disk /dev/sda: 203.9 GB, 203927060480 bytes
255 heads, 63 sectors/track, 24792 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sda1 1 37 297171 83 Linux
/dev/sda2 38 6117 48837600 83 Linux
/dev/sda3 6118 12197 48837600 83 Linux
/dev/sda4 12198 18277 48837600 83 Linux
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
After creating all required partitions, you should now
inform the kernel of the partition changes using
the following syntax as the "root" user account:
# partprobe
# fdisk -l /dev/sda
Disk /dev/sda: 203.9 GB, 203927060480 bytes
255 heads, 63 sectors/track, 24792 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sda1 1 37 297171 83 Linux
/dev/sda2 38 6117 48837600 83 Linux
/dev/sda3 6118 12197 48837600 83 Linux
/dev/sda4 12198 18277 48837600 83 Linux
The FireWire drive (and partitions created) will be exposed
as a SCSI device.
Reboot All Nodes in RAC Cluster
After creating the partitions, it is recommended that you
reboot the kernel on all RAC nodes to make sure that all of the new partitions are
recognized by the kernel on all RAC nodes:
# su -
# reboot
It is not mandatory to reboot each node. However, I have seen issues
when not recycling each machine.
# fdisk -l /dev/sda
Disk /dev/sda: 203.9 GB, 203927060480 bytes
255 heads, 63 sectors/track, 24792 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sda1 1 37 297171 83 Linux
/dev/sda2 38 6117 48837600 83 Linux
/dev/sda3 6118 12197 48837600 83 Linux
/dev/sda4 12198 18277 48837600 83 Linux
Perform the following configuration procedures on all nodes in the cluster!
Several of the commands within this section will need to be performed on every node within the cluster
every time the machine is booted. This section provides very detailed information about setting shared memory,
semaphores, and file handle limits. Instructions for placing them in
a startup script (/etc/rc.local) are included in section
"All Startup Commands for Each RAC Node".
Overview
This section focuses on configuring both Linux servers -
getting each one prepared for the Oracle10g RAC installation. This includes
verifying enough swap space, setting shared memory and semaphores, and finally how to
set the maximum amount of file handles for the O/S.
Swap Space Considerations
(An inadequate amount of swap during the installation
will cause the Oracle Universal Installer to either "hang" or "die")
# dd if=/dev/zero of=tempswap bs=1k count=300000
# chmod 600 tempswap
# mke2fs tempswap
# mkswap tempswap
# swapon tempswap
Setting Shared Memory
Shared memory allows processes to access common structures and data by placing
them in a shared memory segment. This is the fastest form of Inter-Process Communications
(IPC) available - mainly due to the fact that no kernel involvement occurs when data is
being passed between the processes. Data does not need to be copied between processes.
# ipcs -lm
------ Shared Memory Limits --------
max number of segments = 4096
max seg size (kbytes) = 32768
max total shared memory (kbytes) = 8388608
min seg size (bytes) = 1
The SHMMAX parameters defines the maximum size (in bytes) for
a shared memory segment. The Oracle SGA is comprised of shared memory and
it is possible that incorrectly setting SHMMAX could limit the
size of the SGA. When setting SHMMAX, keep in mind that the size of the
SGA should fit within one shared memory segment. An inadequate SHMMAX setting
could result in the following:
ORA-27123: unable to attach to shared memory segment
# cat /proc/sys/kernel/shmmax
33554432
The default value for SHMMAX is 32MB. This is often too small
to configure the Oracle SGA. I generally set the SHMMAX parameter to 2GB
using either of the following methods:
# echo "2147483648" > /proc/sys/kernel/shmmax
# sysctl -w kernel.shmmax=2147483648
# echo "kernel.shmmax=2147483648" >> /etc/sysctl.conf
We now look at the SHMMNI parameters. This kernel parameter is used
to set the maximum number of shared memory segments system wide. The default value
for this parameter is 4096. This value is sufficient and typically does not
need to be changed.
# cat /proc/sys/kernel/shmmni
4096
Finally, we look at the SHMALL shared memory kernel parameter. This parameter
controls the total amount of shared memory (in pages) that can be used at one time on the
system. In short, the value of this parameter should always be at least:
ceil(SHMMAX/PAGE_SIZE)
# cat /proc/sys/kernel/shmall
2097152
The default setting for SHMALL should be adequate for our Oracle10g RAC installation.
The page size in Red Hat Linux on the i386 platform is 4096 bytes. You can, however,
use bigpages which supports the configuration of larger memory page sizes.
Setting Semaphores
Now that we have configured our shared memory settings, it is time to take
care of configuring our semaphores. The best way to describe a semaphore is as
a counter that is used to provide synchronization between processes (or threads within a process)
for shared resources like shared memory. Semaphore sets are supported in System V where each
one is a counting semaphore. When an application requests semaphores, it does so using "sets".
# ipcs -ls
------ Semaphore Limits --------
max number of arrays = 128
max semaphores per array = 250
max semaphores system wide = 32000
max ops per semop call = 32
semaphore max value = 32767
You can also use the following command:
# cat /proc/sys/kernel/sem
250 32000 32 128
The SEMMSL kernel parameter is used to control the
maximum number of semaphores per semaphore set.
The SEMMNI kernel parameter is used to control the
maximum number of semaphore sets in the entire Linux system.
The SEMMNS kernel parameter is used to control the
maximum number of semaphores (not semaphore sets) in the entire Linux system.
SEMMNS -or- (SEMMSL * SEMMNI)
The SEMOPM kernel parameter is used to control the
number of semaphore operations that can be performed per semop system call.
Finally, we see how to set all semaphore parameters using several methods. In the following,
the only parameter I care about changing (raising) is SEMOPM. All other default
settings should be sufficient for our example installation.
# echo "250 32000 100 128" > /proc/sys/kernel/sem
# sysctl -w kernel.sem="250 32000 100 128"
# echo "kernel.sem=250 32000 100 128" >> /etc/sysctl.conf
Setting File Handles
When configuring our Red Hat Linux server, it is critical to ensure that the maximum number
of file handles is large enough. The setting for file handles denotes the number of open
files that you can have on the Linux system.
# cat /proc/sys/fs/file-max
32768
# echo "65536" > /proc/sys/fs/file-max
# sysctl -w fs.file-max=65536
# echo "fs.file-max=65536" >> /etc/sysctl.conf
You can query the current usage of file handles by using the following:
# cat /proc/sys/fs/file-nr
613 95 32768
The file-nr file displays three parameters:
If you need to increase the value in
/proc/sys/fs/file-max,
then make sure that the ulimit is set properly. Usually for 2.4.20 it is set to
unlimited. Verify the ulimit setting my issuing the ulimit command:
# ulimit
unlimited
Setting IP Local Port Range
Configure the system to allow a local port range of 1024 through 65000.
# cat /proc/sys/net/ipv4/ip_local_port_range
32768 61000
The default value for ip_local_port_range is ports 32768 through 61000.
Oracle recommends a local port range of 1024 to 65000.
# echo "1024 65000" > /proc/sys/net/ipv4/ip_local_port_range
# sysctl -w net.ipv4.ip_local_port_range="1024 65000"
# echo "net.ipv4.ip_local_port_range = 1024 65000" >> /etc/sysctl.conf
Setting Shell Limits for the oracle User
To improve the performance of the software on Linux systems, Oracle recommends you increase the
following shell limits for the oracle user:
Shell Limit
Item in limits.conf
Hard Limit
Maximum number of open file descriptors
nofile
65536
Maximum number of processes available to a single user
nproc
16384
cat >> /etc/security/limits.conf <<EOF
oracle soft nproc 2047
oracle hard nproc 16384
oracle soft nofile 1024
oracle hard nofile 65536
EOF
cat >> /etc/pam.d/login <<EOF
session required /lib/security/pam_limits.so
EOF
Update the default shell startup file for the "oracle" UNIX account.
cat >> /etc/profile <<EOF
if [ \$USER = "oracle" ]; then
if [ \$SHELL = "/bin/ksh" ]; then
ulimit -p 16384
ulimit -n 65536
else
ulimit -u 16384 -n 65536
fi
umask 022
fi
EOF
cat >> /etc/csh.login <<EOF
if ( \$USER == "oracle" ) then
limit maxproc 16384
limit descriptors 65536
endif
EOF
Activating All Kernel Parameters for the System
At this point, we have covered all of the required Linux kernel parameters needed
for a successful Oracle installation and configuration. Within each section above, we
configured the Linux system to persist each of the kernel parameters on system
startup by placing them all in the /etc/sysctl.conf file.
# sysctl -p
net.ipv4.ip_forward = 0
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1
net.core.rmem_default = 262144
net.core.wmem_default = 262144
net.core.rmem_max = 262144
net.core.wmem_max = 262144
kernel.shmmax = 2147483648
kernel.sem = 250 32000 100 128
fs.file-max = 65536
net.ipv4.ip_local_port_range = 1024 65000
Perform the following configuration procedures on all nodes in the cluster!
Oracle 9.0.1 and 9.2.0.1 used a userspace watchdog daemon called
watchdogd to monitor the health of the cluster and to
restart a RAC node in case of a failure. Starting with Oracle 9.2.0.2
(and still available in Oracle10g), the
watchdog daemon has been deprecated by a Linux kernel module named
hangcheck-timer which addresses availability and reliability
problems much better. The hang-check timer is loaded into the
Linux kernel and checks if the system hangs. It will set a timer and check the
timer after a certain amount of time. There is a configurable threshold to
hang-check that, if exceeded will reboot the machine. Although
the hangcheck-timer module is not required for Oracle Cluster Ready Services (Cluster Manager)
operation, it is highly recommended by Oracle.
The hangcheck-timer.o Module
The hangcheck-timer module uses a kernel-based timer that
periodically checks the system task scheduler to catch delays in order to
determine the health of the system. If the system hangs or pauses, the timer
resets the node. The hangcheck-timer module uses the Time Stamp Counter
(TSC) CPU register which is a counter that is incremented at each clock signal.
The TCS offers much more accurate time measurements since this register
is updated by the hardware automatically.
Installing the hangcheck-timer.o Module
The hangcheck-timer was normally shipped only by Oracle, however, this
module is now included with Red Hat Linux AS starting with kernel versions
2.4.9-e.12 and higher. If you downloaded and installed the
"Obtaining and Installing a proper Linux Kernel", then the hangcheck-timer is already included for
you. Use the following to ensure that you have the module included:
# find /lib/modules -name "hangcheck-timer.o"
/lib/modules/2.4.21-15.EL/kernel/drivers/char/hangcheck-timer.o
/lib/modules/2.4.21-27.0.2.ELorafw1/kernel/drivers/char/hangcheck-timer.o
In the above output, we care about the hangcheck timer object
(hangcheck-timer.o) in the
/lib/modules/2.4.21-27.0.2.ELorafw1/kernel/drivers/char directory.
Configuring and Loading the hangcheck-timer Module
There are two key parameters to the hangcheck-timer module:
The two hangcheck-timer module parameters indicate how long a RAC node
must hang before it will reset the system. A node reset will occur when
the following is true:
system hang time > (hangcheck_tick + hangcheck_margin)
Configuring Hangcheck Kernel Module Parameters
Each time the hangcheck-timer kernel module is loaded (manually or by Oracle) it needs to know what value to use for
each of the two parameters we just discussed: (hangcheck-tick and hangcheck-margin).
# su -
# echo "options hangcheck-timer hangcheck_tick=30 hangcheck_margin=180" >> /etc/modules.conf
Each time the hangcheck-timer kernel module gets loaded, it will use the values
defined by the entry I made in the /etc/modules.conf file.
Manually Loading the Hangcheck Kernel Module for Testing
Oracle is responsible for loading the hangcheck-timer kernel module when required. It is for this
reason that it is not required to perform a modprobe or insmod of the
hangcheck-timer kernel module in any of the startup files (i.e. /etc/rc.local).
# echo "/sbin/modprobe hangcheck-timer" >> /etc/rc.local
You don't have to manually load the hangcheck-timer kernel module using
modprobe or insmod after each reboot.
The hangcheck-timer module will be loaded by Oracle (automatically) when needed.
# su -
# modprobe hangcheck-timer
# grep Hangcheck /var/log/messages | tail -2
Jan 30 22:11:33 linux1 kernel: Hangcheck: starting hangcheck timer 0.8.0 (tick is 30 seconds, margin is 180 seconds).
Jan 30 22:11:33 linux1 kernel: Hangcheck: Using TSC.
I also like to verify that the correct hangcheck-timer kernel module is
being loaded. To test this, I typically remove the kernel module (if it was
loaded) and then re-loading it using the following:
# su -
# rmmod hangcheck-timer
# insmod hangcheck-timer
Using /lib/modules/2.4.21-27.0.2.ELorafw1/kernel/drivers/char/hangcheck-timer.o
Perform the following configuration procedures on all nodes in the cluster!
When running the Oracle Universal Installer on a RAC node, it will use the
rsh (or ssh) command to copy the Oracle software to all
other nodes within the RAC cluster. The oracle UNIX account on the
node running the Oracle Installer (runInstaller) must be trusted
by all other nodes in your RAC cluster. This means that you should be able to
run the r* commands like rsh, rcp, and rlogin on
the Linux server you will be running the Oracle installer from, against all
other Linux servers in the cluster without a password. The rsh daemon
validates users using the /etc/hosts.equiv file or the .rhosts
file found in the user's (oracle's) home directory.
The use of rcp and rsh are not required for normal
RAC operation. However rcp and rsh should to be enabled for
RAC and patchset installation.
Oracle added support in 10g for using the Secure
Shell (SSH) tool suite for setting up user equivalence. This article, however, uses the older method of
rcp for copying the Oracle software to the other nodes
in the cluster. When using the SSH tool suite, the scp (as opposed to the rcp) command
would be used to copy the software in a very secure manner.
In an effort to get this article out on time, I did not
include instructions for setting up and using the
SSH protocol. I will start using SSH in future articles.
# rpm -q rsh rsh-server
rsh-0.17-17
rsh-server-0.17-17
From the above, we can see that we have the rsh and rsh-server installed.
If rsh is not installed, run the following command from the
CD where the RPM is located:
# su -
# rpm -ivh rsh-0.17-17.i386.rpm rsh-server-0.17-17.i386.rpm
# su -
# chkconfig rsh on
# chkconfig rlogin on
# service xinetd reload
Reloading configuration: [ OK ]
To allow the "oracle" UNIX user account to be trusted among the RAC nodes,
create the /etc/hosts.equiv file on all nodes in the cluster:
# su -
# touch /etc/hosts.equiv
# chmod 600 /etc/hosts.equiv
# chown root.root /etc/hosts.equiv
Now add all RAC nodes to the /etc/hosts.equiv file
similar to the following example for all nodes in the cluster:
# cat /etc/hosts.equiv
+linux1 oracle
+linux2 oracle
+int-linux1 oracle
+int-linux2 oracle
In the above example, the second field permits only the oracle user account to run
rsh commands on the specified nodes. For security reasons,
the /etc/hosts.equiv file should be owned by root and the permissions
should be set to 600. In fact, some systems will only honor the content of
this file if the owner of this file is root and the permissions are set to 600.
Before attempting to test your rsh command, ensure
that you are using the correct version of rsh. By default, Red Hat Linux
puts /usr/kerberos/sbin at the head of the $PATH variable. This
will cause the Kerberos version of rsh to be executed.
# su -
# which rsh
/usr/kerberos/bin/rsh
# cd /usr/kerberos/bin
# mv rsh rsh.original
# which rsh
/usr/bin/rsh
# su - oracle
$ rsh linux1 ls -l /etc/hosts.equiv
-rw------- 1 root root 68 Jan 31 00:39 /etc/hosts.equiv
$ rsh int-linux1 ls -l /etc/hosts.equiv
-rw------- 1 root root 68 Jan 31 00:39 /etc/hosts.equiv
$ rsh linux2 ls -l /etc/hosts.equiv
-rw------- 1 root root 68 Jan 31 00:25 /etc/hosts.equiv
$ rsh int-linux2 ls -l /etc/hosts.equiv
-rw------- 1 root root 68 Jan 31 00:25 /etc/hosts.equiv
Verify that the following startup commands are
included on all nodes in the cluster!
Up to this point, we have talked in great detail about the parameters and resources that
need to be configured on all nodes for the Oracle10g RAC configuration. This section
will take a deep breath and recap those parameters, commands, and entries (in previous sections of this document)
that need to happen on each node when the machine is booted.
All parameters and values to be used by kernel modules.
/etc/modules.conf
alias eth0 tulip
alias eth1 b44
alias sound-slot-0 i810_audio
post-install sound-slot-0 /bin/aumix-minimal -f /etc/.aumixrc -L >/dev/null 2>&1 || :
pre-remove sound-slot-0 /bin/aumix-minimal -f /etc/.aumixrc -S >/dev/null 2>&1 || :
alias usb-controller usb-uhci
alias usb-controller1 ehci-hcd
alias ieee1394-controller ohci1394
options sbp2 sbp2_exclusive_login=0
post-install sbp2 insmod sd_mod
post-install sbp2 insmod ohci1394
post-remove sbp2 rmmod sd_mod
options hangcheck-timer hangcheck_tick=30 hangcheck_margin=180
We wanted to adjust the default and maximum send buffer size as well as the
default and maximum receive buffer size for the interconnect.
/etc/sysctl.conf
# Kernel sysctl configuration file for Red Hat Linux
#
# For binary values, 0 is disabled, 1 is enabled. See sysctl(8) and
# sysctl.conf(5) for more details.
# Controls IP packet forwarding
net.ipv4.ip_forward = 0
# Controls source route verification
net.ipv4.conf.default.rp_filter = 1
# Controls the System Request debugging functionality of the kernel
kernel.sysrq = 0
# Controls whether core dumps will append the PID to the core filename.
# Useful for debugging multi-threaded applications.
kernel.core_uses_pid = 1
# Default setting in bytes of the socket receive buffer
net.core.rmem_default=262144
# Default setting in bytes of the socket send buffer
net.core.wmem_default=262144
# Maximum socket receive buffer size which may be set by using
# the SO_RCVBUF socket option
net.core.rmem_max=262144
# Maximum socket send buffer size which may be set by using
# the SO_SNDBUF socket option
net.core.wmem_max=262144
All machine/IP entries for nodes in the RAC cluster.
/etc/hosts
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost
# Public Network - (eth0)
192.168.1.100 linux1
192.168.1.101 linux2
# Private Interconnect - (eth1)
192.168.2.100 int-linux1
192.168.2.101 int-linux2
# Public Virtual IP (VIP) addresses for - (eth0)
192.168.1.200 vip-linux1
192.168.1.201 vip-linux2
192.168.1.106 melody
192.168.1.102 alex
192.168.1.105 bartman
Allow logins to each node as the oracle user account without
the need for a password.
/etc/hosts.equiv
+linux1 oracle
+linux2 oracle
+int-linux1 oracle
+int-linux2 oracle
Determine which kernel to load by default when the node is booted.
/etc/grub.conf
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/hda2
# initrd /initrd-version.img
#boot=/dev/hda
default=0
timeout=10
splashimage=(hd0,0)/grub/splash.xpm.gz
title White Box Enterprise Linux (2.4.21-27.0.2.ELorafw1)
root (hd0,0)
kernel /vmlinuz-2.4.21-27.0.2.ELorafw1 ro root=LABEL=/
initrd /initrd-2.4.21-27.0.2.ELorafw1.img
title White Box Enterprise Linux (2.4.21-15.EL)
root (hd0,0)
kernel /vmlinuz-2.4.21-15.EL ro root=LABEL=/
initrd /initrd-2.4.21-15.EL.img
These commands are responsible for configuring shared memory,
semaphores, and file handles for use by the Oracle instance.
/etc/rc.local
#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.
touch /var/lock/subsys/local
# +---------------------------------------------------------+
# | SHARED MEMORY |
# +---------------------------------------------------------+
echo "2147483648" > /proc/sys/kernel/shmmax
echo "4096" > /proc/sys/kernel/shmmni
# +---------------------------------------------------------+
# | SEMAPHORES |
# | ---------- |
# | |
# | SEMMSL_value SEMMNS_value SEMOPM_value SEMMNI_value |
# | |
# +---------------------------------------------------------+
echo "256 32000 100 128" > /proc/sys/kernel/sem
# +---------------------------------------------------------+
# | FILE HANDLES |
# ----------------------------------------------------------+
echo "65536" > /proc/sys/fs/file-max
# +---------------------------------------------------------+
# | SETTING IP LOCAL PORT RANGE |
# ----------------------------------------------------------+
echo "1024 65000" > /proc/sys/net/ipv4/ip_local_port_range
# +---------------------------------------------------------+
# | HANGCHECK TIMER |
# | (I do not believe this is required, but doesn't hurt) |
# ----------------------------------------------------------+
/sbin/modprobe hangcheck-timer
Perform the following checks on all nodes in the cluster!
Overview
When installing the Linux O/S (White Box Enterprise Linux or Red Hat Enterprise Linux 3.0), you should verify
that all required RPMs are installed. If you followed the instructions
I used for installing Linux, you would have installed Everything,
in which case you will have all of the required RPM packages. However,
if you performed another installation type (i.e. "Advanced Server), you
may have some packages missing and will need to install them. All
of the required RPMs are on the Linux CDs/ISOs.
Check Required RPMs
The following packages (or higher versions) must be installed.
Reboot the System
make-3.79.1
gcc-3.2.3-34
glibc-2.3.2-95.20
glibc-devel-2.3.2-95.20
glibc-headers-2.3.2-95.20
glibc-kernheaders-2.4-8.34
cpp-3.2.3-34
compat-db-4.0.14-5
compat-gcc-7.3-2.96.128
compat-gcc-c++-7.3-2.96.128
compat-libstdc++-7.3-2.96.128
compat-libstdc++-devel-7.3-2.96.128
openmotif-2.2.2-16
setarch-1.3-1
To query package information (gcc and glibc-devel for example),
use the "rpm -q <PackageName> [, <PackageName>]" command
as follows:
# rpm -q gcc glibc-devel
gcc-3.2.3-34
glibc-devel-2.3.2-95.20
If you need to install any of the above packages (which you should not have
to if you installed Everything), use the "rpm -Uvh <PackageName.rpm>" command.
For example, to install the GCC 3.2.3-24 package, use:
# rpm -Uvh gcc-3.2.3-24.i386.rpm
At this point, reboot all nodes in the cluster before attempting to install any of the Oracle components!!!
# init 6
Most of the configuration procedures in this section
should be performed on all nodes in the cluster!
Creating the OCFS filesystem, however, should only be executed on one of
nodes in the RAC cluster.
Overview
It is now time to install the Oracle Cluster File System (OCFS). OCFS was
developed by Oracle Corporation to remove the burden from DBA's and
System Administrators of having to manage RAW devices. OCFS
provides the same functionality and feel of a normal
file system.
Oracle database files
Online Redo Log Files
Archived Redo Log Files
Control Files
Server Parameter File (SPFILE)
Oracle Cluster Registry (OCR) File
CRS Voting disk
The Linux binaries used to manipulate files and directories
(move, copy, tar, etc.) should not be used on the OCFS file
system. These binaries that are part of the standard system
commands and come with the O/S (i.e. mv, cp, tar, etc.)
cannot be used as they may have a major
performance impact when used on the OCFS file system.
You should instead use Oracle's patched version of these
commands. Keep this in mind when using 3rd vendor backup
tools that also make use of the standard system commands (i.e. mv, tar, etc.).
Oracle Cluster File System - (Part No. B10499-01)
Downloading OCFS
Let's now download the OCFS files (driver, tools, support) from the Oracle Linux Projects Development Group
web site. The main URL for the OCFS project files is:
The page (above) will contain several releases of the OCFS files for
different versions of the Linux kernel. First, download
the key OCFS drivers for either a single processor or a multiple processor
Linux server:
http://oss.oracle.com/projects/ocfs/files/RedHat/RHEL3/i386/
You will also need to download the following two support files:
ocfs-2.4.21-EL-1.0.14-1.i686.rpm - (for single processor)
- OR -
ocfs-2.4.21-EL-smp-1.0.14-1.i686.rpm - (for multiple processors)
ocfs-support-1.0.10-1.i386.rpm - (1.0.10-1 support package)
ocfs-tools-1.0.10-1.i386.rpm - (1.0.10-1 tools package)
If you were curious as to which OCFS driver release you need, use the
OCFS release that matches your kernel version. To determine your kernel release:
$ uname -a
Linux linux1 2.4.21-27.0.2.ELorafw1 #1 Tue Dec 28 16:58:59 PST 2004 i686 i686 i386 GNU/Linux
In the absence of the string "smp" after the string "ELorafw1", we are running a single processor (Uniprocessor)
machine. If the string "smp" were to appear, then you would be running on a multi-processor machine.
I will be installing the OCFS files onto two - single processor machines.
The installation process is simply a matter of running the following
command on all nodes in the cluster as the root user account:
$ su -
# rpm -Uvh ocfs-2.4.21-EL-1.0.14-1.i686.rpm \
ocfs-support-1.0.10-1.i386.rpm \
ocfs-tools-1.0.10-1.i386.rpm
Preparing... ########################################### [100%]
1:ocfs-support ########################################### [ 33%]
2:ocfs-2.4.21-EL ########################################### [ 67%]
Linking OCFS module into the module path [ OK ]
3:ocfs-tools ########################################### [100%]
Configuring and Loading OCFS
The next step is to generate and configure the /etc/ocfs.conf file. The
easiest way to accomplish this is to run the GUI tool ocfstool
This will need to be done on all nodes in the cluster as the root user account:
$ su -
# ocfstool &
This will bring up the GUI as shown below:
Using the ocfstool GUI tool, perform the following steps:
The following dialog shows the settings I used for the node linux1:
After exiting the ocfstool, you will have a /etc/ocfs.conf
similar to the following:
/etc/ocfs.conf
#
# ocfs config
# Ensure this file exists in /etc
#
node_name = int-linux1
ip_address = 192.168.2.100
ip_port = 7000
comm_voting = 1
guid = 8CA1B5076EAF47BE6AA0000D56FC39EC
Notice the guid value. This is a group user
ID that has to be unique for all nodes in the cluster.
Keep in mind also, that the /etc/ocfs.conf could
have been created manually or by simply running
the ocfs_uid_gen -c command that will
assign (or update) the GUID value in the file.
$ su -
# /sbin/load_ocfs
/sbin/insmod ocfs node_name=int-linux1 ip_address=192.168.2.100 cs=1891 guid=8CA1B5076EAF47BE6AA0000D56FC39EC comm_voting=1 ip_port=7000
Using /lib/modules/2.4.21-EL-ABI/ocfs/ocfs.o
Warning: kernel-module version mismatch
/lib/modules/2.4.21-EL-ABI/ocfs/ocfs.o was compiled for kernel version 2.4.21-27.EL
while this kernel is version 2.4.21-27.0.2.ELorafw1
Warning: loading /lib/modules/2.4.21-EL-ABI/ocfs/ocfs.o will taint the kernel: forced load
See http://www.tux.org/lkml/#export-tainted for information about tainted modules
Module ocfs loaded, with warnings
The two warnings (above) can safely be ignored!
To verify that the kernel module was loaded, run the following:
# /sbin/lsmod |grep ocfs
ocfs 299072 0 (unused)
The ocfs module will stay loaded until
the machine is cycled. I will provide instructions
for how to load the module automatically in the
section
Configuring OCFS to Mount Automatically at Startup.
Many types of errors can occur while attempting to load the
ocfs module. For the purpose of this article,
I did not run into any of these problems. I only include them
here for documentation purposes!
One common error looks like this:
# /sbin/load_ocfs
/sbin/insmod ocfs node_name=int-linux1 \
ip_address=192.168.2.100 \
cs=1891 \
guid=8CA1B5076EAF47BE6AA0000D56FC39EC \
comm_voting=1 ip_port=7000
Using /lib/modules/2.4.21-EL-ABI/ocfs/ocfs.o
/lib/modules/2.4.21-EL-ABI/ocfs/ocfs.o: kernel-module version mismatch
/lib/modules/2.4.21-EL-ABI/ocfs/ocfs.o was compiled for kernel version 2.4.21-4.EL
while this kernel is version 2.4.21-15.ELorafw1.
This usually means you have the wrong version of
the modutils RPM. Get the latest version
of modutils and use the following commnad
to update your system:
rpm -Uvh modutils-devel-2.4.25-12.EL.i386.rpm
$ su -
# /lib/modules/`uname -r`/kernel/drivers/addon/ocfs
# ln -s `rpm -qa | grep ocfs-2 | xargs rpm -ql | grep "/ocfs.o$"` \
/lib/modules/`uname -r`/kernel/drivers/addon/ocfs/ocfs.o
Create an OCFS File System
Finally, we can start making use of those partitions we created in
the section
Creating Partitions on the Shared FireWire Storage Device.
Well, at least the first partition!
Unlike the other tasks in this section, creating the OCFS filesystem should only be executed on one of
nodes in the RAC cluster. I will be executing all commands in this section from linux1 only.
$ su -
# mkfs.ocfs -F -b 128 -L /u02/oradata/orcl -m /u02/oradata/orcl -u '175' -g '115' -p 0775 /dev/sda1
Cleared volume header sectors
Cleared node config sectors
Cleared publish sectors
Cleared vote sectors
Cleared bitmap sectors
Cleared data block
Wrote volume header
The following should be noted with the above command:
usage: mkfs.ocfs -b block-size [-C] [-F]
[-g gid] [-h] -L volume-label
-m mount-path [-n] [-p permissions]
[-q] [-u uid] [-V] device
-b Block size in kilo bytes
-C Clear all data blocks
-F Force format existing OCFS volume
-g GID for the root directory
-h Help
-L Volume label
-m Path where this device will be mounted
-n Query only
-p Permissions for the root directory
-q Quiet execution
-u UID for the root directory
-V Print version and exit
One final note about creating OCFS file
systems. You can use the GUI tool ocfstool
to perform the same task as the command-line
mkfs.ocfs. From the ocfstool utility,
use the menu [Tasks] - [Format] .
Mounting the OCFS File System
Now that the file system is created, we can mount it.
Let's first do it using the command-line, then I'll show
how to include it in the /etc/fstab to have it mount
on each boot.
Mounting the file system will need to be performed
on all nodes in the Oracle RAC cluster as the root
user account.
$ su -
# mount -t ocfs /dev/sda1 /u02/oradata/orcl
If the mount was successful, you will simply
got your prompt back. We should, however, run the following
checks to ensure the file system is mounted correctly
with the right permissions. You should run these manual
checks on all nodes in the RAC cluster:
# mount
/dev/hda2 on / type ext3 (rw)
none on /proc type proc (rw)
none on /dev/pts type devpts (rw,gid=5,mode=620)
usbdevfs on /proc/bus/usb type usbdevfs (rw)
/dev/hda1 on /boot type ext3 (rw)
none on /dev/shm type tmpfs (rw)
/dev/sda1 on /u02/oradata/orcl type ocfs (rw)
# ls -ld /u02/oradata/orcl
drwxrwxr-x 1 oracle dba 131072 Feb 2 18:02 /u02/oradata/orcl
Most of the installation and configuration procedures should be
performed on all nodes in the cluster! Creating the ASM disks, however, will
only need to be performed on a single node within the cluster.
Introduction
In this section, we will configure Automatic Storage Management (ASM)
to be used as the file system / volume manager for
all Oracle physical database files (data, online redo logs, control files,
archived redo logs).
(FOR REFERENCE ONLY!) - Methods for Configuring ASM with Linux
This section is nothing more than a reference that describes
the two different methods for configuring ASM on Linux.
The commands in this section are not meant to be run
on any of the nodes in the cluster!
# raw device bindings
# format:
The RAW device bindings will be created on each reboot.
# chown oracle:dba /dev/raw/raw2; chmod 660 /dev/raw/raw2
# chown oracle:dba /dev/raw/raw3; chmod 660 /dev/raw/raw3
# chown oracle:dba /dev/raw/raw4; chmod 660 /dev/raw/raw4
# service rawdevices restart
Downloading the ASMLib Packages
We start this section by downloading the ASMLib libraries and driver from OTN.
Like the Oracle Cluster File System, we need to download the version
for the Linux kernel and number of processors on the machine. We are using
kernel 2.4.21 while the machines I am using are both single processor
machines:
# uname -a
Linux linux1 2.4.21-27.0.2.ELorafw1 #1 Tue Dec 28 16:58:59 PST 2004 i686 i686 i386 GNU/Linux
If you do not currently have an account with Oracle OTN, you
will need to create one. This is a FREE account!
Installing ASMLib Packages
This installation needs to be performed on all nodes in the RAC cluster
as the root user account:
$ su -
# rpm -Uvh oracleasm-2.4.21-EL-1.0.3-1.i686.rpm \
oracleasmlib-1.0.0-1.i386.rpm \
oracleasm-support-1.0.3-1.i386.rpm
Preparing... ########################################### [100%]
1:oracleasm-support ########################################### [ 33%]
2:oracleasm-2.4.21-EL ########################################### [ 67%]
Linking module oracleasm.o into the module path [ OK ]
3:oracleasmlib ########################################### [100%]
Configuring and Loading the ASMLib Packages
Now that we downloaded and installed the ASMLib Packages for Linux,
we now need to configure and load the ASM kernel module. This task
needs to be run on all nodes in the RAC cluster as the
root user account:
$ su -
# /etc/init.d/oracleasm configure
Configuring the Oracle ASM library driver.
This will configure the on-boot properties of the Oracle ASM library
driver. The following questions will determine whether the driver is
loaded on boot and what permissions it will have. The current values
will be shown in brackets ('[]'). Hitting
Creating ASM Disks for Oracle
In the section
"Creating Partitions on the Shared FireWire Storage Device",
we created three Linux partitions to be used for storing Oracle database
files like online redo logs, database files, control files, SPFILEs, and archived redo log files.
Oracle ASM Partitions Created
File System Type
Partition
Size
Mount Point
File Types
ASM
/dev/sda2
50 GB
ORCL:VOL1
Oracle Database Files
ASM
/dev/sda3
50 GB
ORCL:VOL2
Oracle Database Files
ASM
/dev/sda4
50 GB
ORCL:VOL3
Oracle Database Files
Total
150 GB
Creating the ASM disks only needs to be done on one node in the
RAC cluster as the root user account. I will be running these commands on
linux1. On the other nodes, you will need to
perform a scandisk to recognize the new volumes. When
that is complete, you should then run the
oracleasm listdisks command on all nodes
to verify that all ASM disks were created and
available.
If you are repeating this article using the same hardware (actually, the same shared drive),
you may get a failure when attempting to create the ASM disks. If you
do receive a failure, try listing all ASM disks using:
# /etc/init.d/oracleasm listdisks
VOL1
VOL2
VOL3
As you can see, the results show that I have three volumes
already defined. If you have the three volumes already defined
from a previous run, go ahead and remove them using the
following commands. After removing the previously created volumes, use the "oracleasm createdisk" commands (below)
to create the volumes.
# /etc/init.d/oracleasm deletedisk VOL1
Removing ASM disk "VOL1" [ OK ]
# /etc/init.d/oracleasm deletedisk VOL2
Removing ASM disk "VOL2" [ OK ]
# /etc/init.d/oracleasm deletedisk VOL3
Removing ASM disk "VOL3" [ OK ]
$ su -
# /etc/init.d/oracleasm createdisk VOL1 /dev/sda2
Marking disk "/dev/sda2" as an ASM disk [ OK ]
# /etc/init.d/oracleasm createdisk VOL2 /dev/sda3
Marking disk "/dev/sda3" as an ASM disk [ OK ]
# /etc/init.d/oracleasm createdisk VOL3 /dev/sda4
Marking disk "/dev/sda4" as an ASM disk [ OK ]
On all other nodes in the RAC cluster, you must perform
a scandisk to recognize the new volumes:
# /etc/init.d/oracleasm scandisks
Scanning system for ASM disks [ OK ]
We can now test that the ASM disks were successfully created by
using the following command on all nodes in the RAC cluster
as the root user account:
# /etc/init.d/oracleasm listdisks
VOL1
VOL2
VOL3
The following download procedures only need to be performed on
one node in the cluster!
Overview
The next logical step is to install Oracle Cluster Ready Services (10.1.0.3.0)
and the Oracle Database 10g R1 (10.1.0.3.0) software. However, we must first download
and extract the required Oracle software packages from the Oracle Technology Network (OTN).
If you do not currently have an account with Oracle OTN, you
will need to create one. This is a FREE account!
Oracle Database 10g Release 1 (10.1.0.3) for Linux x86
First, download the Oracle Database 10g Release 1 (10.1.0.3) Software for Linux x86.
Oracle Database 10g Release 1 (10.1.0.3) (Enterprise/Standard Edition for Linux x86)
Oracle Cluster Ready Services Release 1 (10.1.0.3) for Linux x86
Next, we need to download the Oracle Cluster Ready Services (OCRS) for Linux x86.
This can be downloaded from the same page used to download the
Oracle Database Server:
Oracle Cluster Ready Services Release 1 (10.1.0.3) (Enterprise/Standard Edition for Linux x86)
As the "oracle" user account, extract the two packages you downloaded to
a temporary directory. In this example, I will use "/u01/app/oracle/orainstall/crs"
and "/u01/app/oracle/orainstall/db".
# su - oracle
$ cd ~oracle/orainstall/crs
$ gunzip ship.crs.lnx32.cpio.gz
$ cpio -idmv < ship.crs.lnx32.cpio
$ cd ~oracle/orainstall/db
$ gunzip ship.db.lnx32.cpio.gz
$ cpio -idmv < ship.db.lnx32.cpio
Some browsers may uncompress the files during download but leave the extension the same
(gz). If the above steps do not work for you, try
to rename the file(s) by removing the gz extension and simply extracting the file.
Perform the following installation procedures on only one node in the cluster!
The Oracle CRS software will be installed to all other nodes in the
cluster by the Oracle Universal Installer.
Overview
We are ready to install the Cluster part of the environment -
the Cluster Ready Services (CRS). In the last section, we
downloaded and extracted the install files for CRS to linux1 in
the directory /u01/app/oracle/orainstall/crs/Disk1. This is the only
node we need to perform the install from. During the installation of CRS, you
will be asked for the nodes involved and to configure in the RAC cluster.
Once the actual installation starts, it will copy the required software to
all nodes using the remote access we configured in the section
"Configuring RAC Nodes for Remote Access".
$ ps -ef | grep crs
root 4661 1 0 14:18 ? 00:00:00 /bin/su -l oracle -c exec /u01/app/oracle/product/10.1.0/crs/bin/evmd
root 4664 1 0 14:18 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/crsd.bin
root 4862 4663 0 14:18 ? 00:00:00 /bin/su -l oracle -c /u01/app/oracle/product/10.1.0/crs/bin/ocssd || exit 137
oracle 4864 4862 0 14:18 ? 00:00:00 -bash -c /u01/app/oracle/product/10.1.0/crs/bin/ocssd || exit 137
oracle 4898 4864 0 14:18 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/ocssd.bin
oracle 4901 4661 0 14:18 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/evmd.bin
root 4908 4664 0 14:18 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/crsd.bin -1
oracle 4947 4901 0 14:18 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/evmd.bin
oracle 4949 4898 0 14:18 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/ocssd.bin
...
oracle 4958 4949 0 14:19 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/ocssd.bin
oracle 4959 4947 0 14:19 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/evmd.bin
...
oracle 4983 4947 0 14:19 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/evmd.bin
oracle 4984 4983 0 14:19 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/evmlogger.bin \
-o /u01/app/oracle/product/10.1.0/crs/evm/log/evmlogger.info \
-l /u01/app/oracle/product/10.1.0/crs/evm/log/evmlogger.log
oracle 4985 4947 0 14:19 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/evmd.bin
...
oracle 4990 4947 0 14:19 ? 00:00:00 /u01/app/oracle/product/10.1.0/crs/bin/evmd.bin
Cluster Ready Services Shared Files
The two shared files used by CRS will be stored on the Oracle Cluster
File System we created earlier. The two shared CRS files are:
For the installation that I am performing in this article, it is not possible to use
Automatic Storage Management (ASM) for the two CRS files;
Oracle Cluster Registry (OCR) or the CRS Voting Disk files. The problem is
that these files need to be in place and accessible BEFORE any Oracle instances can be started. For
ASM to be available, the ASM instance would need to be run first.
The two shared files could be stored on the OCFS, shared RAW devices, or another vendor's clustered file system.
Verifying Environment Variables
Before starting the Oracle Universal Installer, you should first run
the xhost command as root from the console to
allow X Server connections. Then unset
the ORACLE_HOME variable and verify that each of the nodes in
the RAC cluster defines a unique ORACLE_SID. We also should verify
that we are logged in as the oracle user account:
# xhost +
access control disabled, clients can connect from any host
# su - oracle
$ unset ORA_CRS_HOME
$ unset ORACLE_HOME
$ unset ORA_NLS10
$ unset TNS_ADMIN
$ env | grep ORA
ORACLE_SID=orcl1
ORACLE_BASE=/u01/app/oracle
ORACLE_TERM=xterm
$ env | grep ORA
ORACLE_SID=orcl2
ORACLE_BASE=/u01/app/oracle
ORACLE_TERM=xterm
Installing Cluster Ready Services
CSS Timeout Computation in 10g RAC 10.1.0.3
clssnmDiskPingMonitorThread: voting device access hanging (45010 miliseconds)
The problem is essentially slow disks and the default value for CSS misscount.
The CSS misscount value is the number of heartbeats missed before CSS evicts a node. CSS uses
this number to calculate the time after which an I/O to the voting disk should be considered
timed out and thus terminating itself to prevent split brain conditions. The default value for CSS misscount
on Linux for Oracle 10.1.0.2, 10.1.0.3, an 10.1.0.4 is 60.
The formula for calculating the timeout value (in seconds), however,
did change from release 10.1.0.2 to 10.1.0.3.
time_in_secs > CSS misscount, then EXIT
With the default value of 60, for example,
the timeout period would be 60 seconds.
disktimeout_in_secs = MAX((3 * CSS misscount)/4, CSS misscount - 15)
Again, using the default CSS misscount value of 60, this would result in a timeout of 45 seconds.
$ cd ~oracle
$ ./orainstall/crs/Disk1/runInstaller -ignoreSysPrereqs
Starting Oracle Universal Installer...
Checking installer requirements...
Checking operating system version: must be redhat-2.1, redhat-3, SuSE-9, SuSE-8 or UnitedLinux-1.0
Failed <<<<
>>> Ignoring required pre-requisite failures. Continuing...
Preparing to launch Oracle Universal Installer from /tmp/OraInstall2005-02-05_06-14-20PM. Please wait ...
Screen Name
Response
Welcome Screen
Click Next
Specify Inventory directory and credentials
Accept the default values:
Inventory directory: /u01/app/oracle/oraInventory
Operating System group name: dba
Root Script Window - Run orainstRoot.sh
Open a new console window on the node you are performing the
install on as the "root" user account.
Specify File Locations
Leave the default value for the Source directory.
Set the destination for the ORACLE_HOME name and location
as follows:
Name: OraCrs10g_home1
Location: /u01/app/oracle/product/10.1.0/crs
Language Selection
I accepted the default value:
Selected Languages: English
Cluster Configuration
Cluster Name: crs
Public Node Name: linux1 Private Node Name: int-linux1
Public Node Name: linux2 Private Node Name: int-linux2
Specify Network Interface Usage
Interface Name: eth0 Subnet: 192.168.1.0 Interface Type: Public
Interface Name: eth1 Subnet: 192.168.2.0 Interface Type: Private
Oracle Cluster Registry
Specify OCR Location: /u02/oradata/orcl/OCRFile
Voting Disk
Enter voting disk file name: /u02/oradata/orcl/CSSFile
Root Script Window - Run orainstRoot.sh
Open a new console window on each node in the RAC cluster
as the "root" user account.
Summary
For some reason, the OUI fails to create a "$ORACLE_HOME/log" for the installation directory
before starting the installation. You should manually create this directory
before clicking the "Install" button.
Root Script Window - Run root.sh
After the installation has completed, you will be prompted
to run the root.sh script.
Navigate to the /u01/app/oracle/product/10.1.0/crs directory
and locate the root.sh file for each node in the cluster. As
mentioned earilier in the
"CSS Timeout Computation in 10g RAC 10.1.0.3"
section, you should modify the entry for CSS misscount from 60 to 180 as follows. Change the
following entry that can be found on line 351:
...
CSS is active on these nodes.
linux1
linux2
CSS is active on all nodes.
Oracle CRS stack installed and running under init(1M)
End of installation
At the end of the installation, exit from the OUI.
Verifying Cluster Ready Services / CSS misscount value
As previously discussed in the section
"CSS Timeout Computation in 10g RAC 10.1.0.3",
I mentioned the need to modify the CSS misscount value from its default value of 60 to 180 (or higher).
Within that section I disscussed how this can be accomplished by modifying the
root.sh
script before running it on each node in the cluster. If you were not able to modify the CSS misscount
value within the root.sh script, you can still perform this action by using the
$ORA_CRS_HOME/bin/crsctl program. For example, to obtain the current value for CSS misscount,
use the following:
$ORA_CRS_HOME/bin/crsctl get css misscount
Configuration parameter misscount has value of 180.
If you get back a value of 60, you will want to modify it to 180 as follows:
$ORA_CRS_HOME/bin/crsctl set css misscount 180
Verifying Cluster Ready Services Installation
After the installation of CRS, we can run through several tests to
verify the install was successful. Run the following commands
on all nodes in the RAC cluster.
Check CRS Auto-Start Scripts
$ /u01/app/oracle/product/10.1.0/crs/bin/olsnodes -n
linux1 1
linux2 2
$ ls -l /etc/init.d/init.*
-r-xr-xr-x 1 root root 1207 Feb 5 19:41 /etc/init.d/init.crs*
-r-xr-xr-x 1 root root 5492 Feb 5 19:41 /etc/init.d/init.crsd*
-r-xr-xr-x 1 root root 18617 Feb 5 19:41 /etc/init.d/init.cssd*
-r-xr-xr-x 1 root root 4553 Feb 5 19:41 /etc/init.d/init.evmd*
Perform the following installation procedures on only one node in the cluster!
The Oracle database software will be installed to all other nodes in the
cluster by the Oracle Universal Installer.
Overview
After successfully installing the Oracle Cluster Ready Services (CRS) Software, the next
step is to install the Oracle10g Database Software (10.1.0.3) with Real Application Clusters (RAC).
At the time of this writing, the OUI for Oracle10g was unable to discover
disks/volumes that were marked as Linux ASMLib. Because of this, we will forgoe
the "Create Database" option when installing the Oracle10g software. We will,
instead, create the database using the Database Creation Assistant (DBCA) after the
Oracle10g Database Software install.
Verifying Environment Variables
Before starting the Oracle Universal Installer, you should first run
the xhost command as root from the console to
allow X Server connections. Then unset
the ORACLE_HOME variable and verify that each of the nodes in
the RAC cluster defines a unique ORACLE_SID. We also should verify
that we are logged in as the oracle user account:
# xhost +
access control disabled, clients can connect from any host
# su - oracle
$ unset ORA_CRS_HOME
$ unset ORACLE_HOME
$ unset ORA_NLS10
$ unset TNS_ADMIN
$ env | grep ORA
ORACLE_SID=orcl1
ORACLE_BASE=/u01/app/oracle
ORACLE_TERM=xterm
$ env | grep ORA
ORACLE_SID=orcl2
ORACLE_BASE=/u01/app/oracle
ORACLE_TERM=xterm
Installing Oracle10g Database Software
The following tasks are used to install the Oracle10g Database Software:
$ cd ~oracle
$ /u01/app/oracle/orainstall/db/Disk1/runInstaller -ignoreSysPrereqs
Starting Oracle Universal Installer...
Checking installer requirements...
Checking operating system version: must be redhat-2.1, redhat-3, SuSE-9, SuSE-8 or UnitedLinux-1.0
Failed <<<<
>>> Ignoring required pre-requisite failures. Continuing...
Preparing to launch Oracle Universal Installer from /tmp/OraInstall2005-02-07_03-14-28PM. Please wait ...
$ Oracle Universal Installer, Version 10.1.0.3.0 Production
Copyright (C) 1999, 2004, Oracle. All rights reserved.
Screen Name
Response
Welcome Screen
Click Next
Specify File Locations
Ensure that the "Source Path:" is pointing to
the "products.xml" file for the ".../db/Disk1/stage/product.xml"
product installation files.
Name: OraDb10g_home1
Location: /u01/app/oracle/product/10.1.0/db_1
Specify Hardware Cluster Installation Mode
Select the Cluster Installation option
then select all nodes available.
Click Select All to select all servers: linux1 and linux2.
If the installation stops here and the status of any of the
RAC nodes is "Node not reachable", perform the following checks:
Select Installation Type
I selected the Enterprise Edition option.
Select Database Configuration
Select the option to Do not create a starter database.
Summary
For some reason, the OUI fails to create a "$ORACLE_HOME/log" for the installation directory
before starting the installation. You should manually create this directory
before clicking the "Install" button.
Root Script Window - Run root.sh
After the installation has completed, you will be prompted
to run the root.sh script. It is important to keep in mind
that the root.sh script will need to be run ON ALL NODES
in the RAC cluster ONE AT A TIME starting
with the node you are running the database installation from.
Before running the
root.sh script on the first Linux server, ensure that the console window you are using
can run a GUI utility. (Set your $DISPLAY environment variable before running
the root.sh script!)
Network interfaces: Select both interfaces - eth0 and eth1
Virtual IPs for cluster nodes:
Node Name: linux1
IP Alias Name: vip-linux1
IP Address: 192.168.1.200
Subnet Mask: 255.255.255.0
IP Alias Name: vip-linux2
IP Address: 192.168.1.201
Subnet Mask: 255.255.255.0
Configuration Assistant Progress Dialog: Click OK after configuration is complete.
Configuration Results: Click Exit
End of installation
At the end of the installation, exit from the OUI.
Perform the following configuration procedures
on only one node in the cluster!
The Network Configuration Assistant (NETCA) will setup the TNS
listener in a clustered configuration on all nodes in the cluster.
The Database Configuration Assistant (DBCA) requires the Oracle TNS Listener
process to be configured and running on all nodes in the RAC cluster before it can
create the clustered database.
Before running the Network Configuration Assistant (NETCA), make sure to
re-login as the oracle user and verify the $ORACLE_HOME environment variable set
to the proper location. If you attempt to use the console window
used in the previous section, (Installing Oracle10g Database
Software), remember that we unset the $ORACLE_HOME environment variable.
This will result in a failure when attempting to run netca.
$ netca &
Screen Name
Response
Select the Type of Oracle
Net Services Configuration
Select Cluster Configuration
Select the nodes to configure
Select all of the nodes: linux1 and linux2.
Type of Configuration
Select Listener configuration.
Listener Configuration - Next 6 Screens
The following screens are now like any other normal listener configuration. You can simply
accept the default parameters for the next six screens:
What do you want to do: Add
Listener name: LISTENER
Selected protocols: TCP
Port number: 1521
Configure another listener: No
Listener configuration complete! [ Next ]
You will be returned to this Welcome (Type of Configuration) Screen.
Type of Configuration
Select Naming Methods configuration.
Naming Methods Configuration
The following screens are:
Selected Naming Methods: Local Naming
Naming Methods configuration complete! [ Next ]
You will be returned to this Welcome (Type of Configuration) Screen.
Type of Configuration
Click Finish to exit the NETCA.
The Oracle TNS listener process should now be running on all nodes in the RAC
cluster:
$ hostname
linux1
$ ps -ef | grep lsnr | grep -v 'grep' | grep -v 'ocfs' | awk '{print $9}'
LISTENER_LINUX1
=====================
$ hostname
linux2
$ ps -ef | grep lsnr | grep -v 'grep' | grep -v 'ocfs' | awk '{print $9}'
LISTENER_LINUX2
The database creation process should only be performed
from one node in the cluster!
Overview
We will be using the Oracle Database Configuration Assistant (DBCA) to create
the clustered database.
Creating the Clustered Database
To start the database creation process, run the following:
# xhost +
access control disabled, clients can connect from any host
# su - oracle
$ dbca &
Screen Name
Response
Welcome Screen
Select Oracle Real Application Clusters database.
Operations
Select Create a Database.
Node Selection
Click the Select All button to
select all servers: linux1 and linux2.
Database Templates
Select Custom Database
Database Identification
Select:
Global Database Name: orcl.idevelopment.info
SID Prefix: orcl
I used idevelopment.info for the database domain. You
may use any domain. Keep in mind that this domain does not have to be
a valid DNS domain.
Management Option
Leave the default options here which is to
Configure the Database with Enterprise Manager /
Use Database Control for Database Management
Database Credentials
I selected to Use the Same Password for All Accounts.
Enter the password (twice) and make sure the password does not start with a digit number.
Storage Options
For this article, we will select to use Automatic Storage Management (ASM).
Create ASM Instance
Other than supplying the SYS password I wanted to use for this instance, all other options
I used were the defaults. This includes the default for all ASM parameters and then
to use default parameter file (IFILE): {ORACLE_BASE}/admin/+ASM/pfile/init.ora.
ASM Disk Groups
To start, click the Create New button.
This will bring up the "Create Disk Group" window with the three volumes
we configured earlier using ASMLib.
Database File Locations
I selected to use the default which is Use Oracle-Managed Files:
Database Area: +ORCL_DATA1
Recovery Configuration
Using recovery options like Flash Recovery Area is out of scope for this article.
I did not select any recovery options.
Database Content
I left all of the Database Components (and destination tablespaces) set to their default
value.
Database Services
For this test configuration, click Add,
and enter the Service Name: orcltest.
Leave both instances set to Preferred and for
the "TAF Policy" select Basic.
Initialization Parameters
Change any parameters for your environment. I left them all at their default settings.
Database Storage
Change any parameters for your environment. I left them all at their default settings.
Creation Options
Keep the default option Create Database selected and click
Finish to start the database creation process.
You may receive an error message during the install.
End of Database Creation
At the end of the database creation, exit from the DBCA.
Creating the orcltest Service
During the creation of the Oracle clustered database, we added a service
named "orcltest" that will be used to connect to the database
with TAF enabled. During several of my installs, the service was added to the
tnsnames.ora, but was never updated as a service for each
Oracle instance.
SQL> show parameter service
NAME TYPE VALUE
-------------------- ----------- --------------------------------
service_names string orcl.idevelopment.info, orcltest
SQL> show parameter service
NAME TYPE VALUE
-------------------- ----------- --------------------------
service_names string orcl.idevelopment.info
SQL> alter system set service_names =
2 'orcl.idevelopment.info, orcltest.idevelopment.info' scope=both;
Ensure that the TNS networking files are configured on all
nodes in the cluster!
listener.ora
We already covered how to create a TNS listener configuration file (listener.ora)
for a clustered environment in the section
Creating TNS Listener Process.
The listener.ora file should be properly configured and no modifications should
be needed.
listener.ora
# listener.ora.linux1 Network Configuration File:
# /u01/app/oracle/product/10.1.0/db_1/network/admin/listener.ora.linux1
# Generated by Oracle configuration tools.
LISTENER_LINUX1 =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux1)(PORT = 1521)(IP = FIRST))
)
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.100)(PORT = 1521)(IP = FIRST))
)
)
)
SID_LIST_LISTENER_LINUX1 =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = /u01/app/oracle/product/10.1.0/db_1)
(PROGRAM = extproc)
)
)
tnsnames.ora
Here is a copy of my tnsnames.ora file that was
configured by Oracle and can be used for testing the Transparent Application Failover (TAF).
This file should already be configured on each node in the
RAC cluster.
tnsnames.ora
# tnsnames.ora Network Configuration File:
# /u01/app/oracle/product/10.1.0/db_1/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.
LISTENERS_ORCL =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux1)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux2)(PORT = 1521))
)
ORCL2 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux2)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl.idevelopment.info)
(INSTANCE_NAME = orcl2)
)
)
ORCL1 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux1)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl.idevelopment.info)
(INSTANCE_NAME = orcl1)
)
)
ORCLTEST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux1)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux2)(PORT = 1521))
(LOAD_BALANCE = yes)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcltest.idevelopment.info)
(FAILOVER_MODE =
(TYPE = SELECT)
(METHOD = BASIC)
(RETRIES = 180)
(DELAY = 5)
)
)
)
ORCL =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux1)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux2)(PORT = 1521))
(LOAD_BALANCE = yes)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl.idevelopment.info)
)
)
Connecting to Clustered Database From an External Client
This is an optional step, but I like to perform it in order to verify
my TNS files are configured correctly. Use another machine (i.e. a Windows machine connected to
the network) that has Oracle
installed (either 9i or 10g) and add the TNS entries
(in the tnsnames.ora) from either of the nodes in the cluster that were created
for the clustered database.
C:\> sqlplus system/manager@orcl2
C:\> sqlplus system/manager@orcl1
C:\> sqlplus system/manager@orcltest
C:\> sqlplus system/manager@orcl
When creating the clustered database, we left all tablespaces set
to their default size. Since I am using a large drive for the
shared storage, I like to make a sizable testing database.
$ sqlplus "/ as sysdba"
SQL> create user scott identified by tiger default tablespace users;
SQL> grant dba, resource, connect to scott;
SQL> alter database datafile '+ORCL_DATA1/orcl/datafile/users.264.1' resize 1024m;
SQL> alter tablespace users add datafile '+ORCL_DATA1' size 1024m autoextend off;
SQL> create tablespace indx datafile '+ORCL_DATA1' size 1024m
2 autoextend on next 50m maxsize unlimited
3 extent management local autoallocate
4 segment space management auto;
SQL> alter database datafile '+ORCL_DATA1/orcl/datafile/system.259.1' resize 800m;
SQL> alter database datafile '+ORCL_DATA1/orcl/datafile/sysaux.261.1' resize 500m;
SQL> alter tablespace undotbs1 add datafile '+ORCL_DATA1' size 1024m
2 autoextend on next 50m maxsize 2048m;
SQL> alter tablespace undotbs2 add datafile '+ORCL_DATA1' size 1024m
2 autoextend on next 50m maxsize 2048m;
SQL> alter database tempfile '+ORCL_DATA1/orcl/tempfile/temp.262.1' resize 1024m;
Status Tablespace Name TS Type Ext. Mgt. Seg. Mgt. Tablespace Size Used (in bytes) Pct. Used
--------- --------------- ------------ ---------- --------- ---------------- ---------------- ---------
ONLINE INDX PERMANENT LOCAL AUTO 1,073,741,824 65,536 0
ONLINE SYSAUX PERMANENT LOCAL AUTO 524,288,000 227,803,136 43
ONLINE SYSTEM PERMANENT LOCAL MANUAL 838,860,800 449,380,352 54
ONLINE UNDOTBS1 UNDO LOCAL MANUAL 1,283,457,024 184,745,984 14
ONLINE UNDOTBS2 UNDO LOCAL MANUAL 1,283,457,024 4,194,304 0
ONLINE USERS PERMANENT LOCAL AUTO 2,147,483,648 131,072 0
ONLINE TEMP TEMPORARY LOCAL MANUAL 1,073,741,824 22,020,096 2
---------------- ---------------- ---------
avg 16
sum 8,225,030,144 888,340,480
7 rows selected.
The following RAC verification checks should be performed
on all nodes in the cluster! For this article, I will only
be performing checks from linux1.
Overview
This section provides several srvctl commands and SQL queries that can be used
to validate your Oracle10g RAC configuration.
There are five node-level tasks defined for SRVCTL:
Status of all instances and services
$ srvctl status database -d orcl
Instance orcl1 is running on node linux1
Instance orcl2 is running on node linux2
Status of a single instance
$ srvctl status instance -d orcl -i orcl2
Instance orcl2 is running on node linux2
Status of a named service globally across the database
$ srvctl status service -d orcl -s orcltest
Service orcltest is running on instance(s) orcl2, orcl1
Status of node applications on a particular node
$ srvctl status nodeapps -n linux1
VIP is running on node: linux1
GSD is running on node: linux1
Listener is running on node: linux1
ONS daemon is running on node: linux1
Status of an ASM instance
$ srvctl status asm -n linux1
ASM instance +ASM1 is running on node linux1.
List all configured databases
$ srvctl config database
orcl
Display configuration for our RAC database
$ srvctl config database -d orcl
linux1 orcl1 /u01/app/oracle/product/10.1.0/db_1
linux2 orcl2 /u01/app/oracle/product/10.1.0/db_1
Display all services for the specified cluster database
$ srvctl config service -d orcl
orcltest PREF: orcl2 orcl1 AVAIL:
Display the configuration for node applications - (VIP, GSD, ONS, Listener)
$ srvctl config nodeapps -n linux1 -a -g -s -l
VIP exists.: /vip-linux1/192.168.1.200/255.255.255.0/eth0:eth1
GSD exists.
ONS daemon exists.
Listener exists.
Display the configuration for the ASM instance(s)
$ srvctl config asm -n linux1
+ASM1 /u01/app/oracle/product/10.1.0/db_1
All running instances in the cluster
SELECT
inst_id
, instance_number inst_no
, instance_name inst_name
, parallel
, status
, database_status db_status
, active_state state
, host_name host
FROM gv$instance
ORDER BY inst_id;
INST_ID INST_NO INST_NAME PAR STATUS DB_STATUS STATE HOST
-------- -------- ---------- --- ------- ------------ --------- -------
1 1 orcl1 YES OPEN ACTIVE NORMAL linux1
2 2 orcl2 YES OPEN ACTIVE NORMAL linux2
All data files which are in the disk group
select name from v$datafile
union
select member from v$logfile
union
select name from v$controlfile
union
select name from v$tempfile;
NAME
-------------------------------------------
+ORCL_DATA1/orcl/controlfile/current.256.1
+ORCL_DATA1/orcl/datafile/indx.269.1
+ORCL_DATA1/orcl/datafile/sysaux.261.1
+ORCL_DATA1/orcl/datafile/system.259.1
+ORCL_DATA1/orcl/datafile/undotbs1.260.1
+ORCL_DATA1/orcl/datafile/undotbs1.270.1
+ORCL_DATA1/orcl/datafile/undotbs2.263.1
+ORCL_DATA1/orcl/datafile/undotbs2.271.1
+ORCL_DATA1/orcl/datafile/users.264.1
+ORCL_DATA1/orcl/datafile/users.268.1
+ORCL_DATA1/orcl/onlinelog/group_1.257.1
+ORCL_DATA1/orcl/onlinelog/group_2.258.1
+ORCL_DATA1/orcl/onlinelog/group_3.265.1
+ORCL_DATA1/orcl/onlinelog/group_4.266.1
+ORCL_DATA1/orcl/tempfile/temp.262.1
15 rows selected.
All ASM disk that belong to the 'ORCL_DATA1' disk group
SELECT path
FROM v$asm_disk
WHERE group_number IN (select group_number
from v$asm_diskgroup
where name = 'ORCL_DATA1');
PATH
----------------------------------
ORCL:VOL1
ORCL:VOL2
ORCL:VOL3
At this point, everything has been installed and configured
for Oracle10g RAC. We have all of the required software
installed and configured plus we have a fully functional
clustered database.
# su - oracle
$ hostname
linux1
Stopping the Oracle10g RAC Environment
The first step is to stop the Oracle instance. Once the instance (and related services)
is down, then bring down the ASM instance. Finally, shutdown
the node applications (Virtual IP, GSD, TNS Listener, and ONS).
$ export ORACLE_SID=orcl1
$ emctl stop dbconsole
$ srvctl stop instance -d orcl -i orcl1
$ srvctl stop asm -n linux1
$ srvctl stop nodeapps -n linux1
Starting the Oracle10g RAC Environment
The first step is to start the node applications (Virtual IP, GSD, TNS Listener, and ONS).
Once the node applications are successfully started, then bring up the ASM instance.
Finally, bring up the Oracle instance (and related services) and the
Enterprise Manager Database console.
$ export ORACLE_SID=orcl1
$ srvctl start nodeapps -n linux1
$ srvctl start asm -n linux1
$ srvctl start instance -d orcl -i orcl1
$ emctl start dbconsole
Start / Stop All Instances with SRVCTL
Start / Stop all of the instances and its enabled services. I just included
this for fun as a way to bring down all instances!
$ srvctl start database -d orcl
$ srvctl stop database -d orcl
Overview
It is not uncommon for businesses of today to demand 99.99% or even 99.999%
availability for their enterprise applications. Think about what it would take
to ensure a downtime of no more than .5 hours or even no downtime during the year.
To answer many of these high availability requirements, businesses are investing in
mechanisms that provide for automatic failover when one participating system fails. When
considering the availability of the Oracle database, Oracle10g RAC provides
a superior solution with its advanced failover mechanisms. Oracle10g RAC
includes the required components that all work within a clustered configuration
responsible for providing continuous availability - when one of the participating
systems fail within the cluster, the users are automatically migrated to the other available systems.
Keep in mind that at the time of this article, using the Java thin client
will not be able to participate in TAF since it never reads the tnsnames.ora file.
Before demonstrating TAF, we need to verify that a valid entry exists in the tnsnames.ora file
on a non-RAC client machine (if you have a Windows machine lying around).
Ensure that you have Oracle RDBMS software installed. (Actually, you only
need a client install of the Oracle software.)
tnsnames.ora File Entry for Clustered Database
...
ORCLTEST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux1)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = vip-linux2)(PORT = 1521))
(LOAD_BALANCE = yes)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcltest.idevelopment.info)
(FAILOVER_MODE =
(TYPE = SELECT)
(METHOD = BASIC)
(RETRIES = 180)
(DELAY = 5)
)
)
)
...
The following SQL query can be used to check a session's failover type,
failover method, and if a failover has occurred. We will be using this
query throughout this example.
COLUMN instance_name FORMAT a13
COLUMN host_name FORMAT a9
COLUMN failover_method FORMAT a15
COLUMN failed_over FORMAT a11
SELECT
instance_name
, host_name
, NULL AS failover_type
, NULL AS failover_method
, NULL AS failed_over
FROM v$instance
UNION
SELECT
NULL
, NULL
, failover_type
, failover_method
, failed_over
FROM v$session
WHERE username = 'SYSTEM';
From a Windows machine (or other non-RAC client machine), login to the clustered database using the
orcltest service
as the SYSTEM user:
C:\> sqlplus system/manager@orcltest
COLUMN instance_name FORMAT a13
COLUMN host_name FORMAT a9
COLUMN failover_method FORMAT a15
COLUMN failed_over FORMAT a11
SELECT
instance_name
, host_name
, NULL AS failover_type
, NULL AS failover_method
, NULL AS failed_over
FROM v$instance
UNION
SELECT
NULL
, NULL
, failover_type
, failover_method
, failed_over
FROM v$session
WHERE username = 'SYSTEM';
INSTANCE_NAME HOST_NAME FAILOVER_TYPE FAILOVER_METHOD FAILED_OVER
------------- --------- ------------- --------------- -----------
orcl1 linux1
SELECT BASIC NO
DO NOT logout of the above SQL*Plus session!
Now that we have run the query (above), we should now shutdown the
instance orcl1 on linux1 using
the abort option. To perform this operation, we can
use the srvctl command-line utility as follows:
# su - oracle
$ srvctl status database -d orcl
Instance orcl1 is running on node linux1
Instance orcl2 is running on node linux2
$ srvctl stop instance -d orcl -i orcl1 -o abort
$ srvctl status database -d orcl
Instance orcl1 is not running on node linux1
Instance orcl2 is running on node linux2
Now let's go back to our SQL session and rerun the SQL statement
in the buffer:
COLUMN instance_name FORMAT a13
COLUMN host_name FORMAT a9
COLUMN failover_method FORMAT a15
COLUMN failed_over FORMAT a11
SELECT
instance_name
, host_name
, NULL AS failover_type
, NULL AS failover_method
, NULL AS failed_over
FROM v$instance
UNION
SELECT
NULL
, NULL
, failover_type
, failover_method
, failed_over
FROM v$session
WHERE username = 'SYSTEM';
INSTANCE_NAME HOST_NAME FAILOVER_TYPE FAILOVER_METHOD FAILED_OVER
------------- --------- ------------- --------------- -----------
orcl2 linux2
SELECT BASIC YES
SQL> exit
From the above demonstration, we can see that the above session
has now been failed over to instance orcl2 on
linux2.
Oracle10g RAC allows the DBA to configure a database solution with superior
fault tolerance and load balancing. For those DBAs, however, that want to
become more familiar with the features and benefits of Oracle10g RAC will
find the costs of configuring even a small RAC cluster costing in the
range of $15,000 to $20,000.
An article of this magnitude and complexity is generally not the work
of one person alone. Although I was able to author and successfully
demonstrate the validity of the components that make up this configuration,
there are several other individuals that deserve credit in making this article a success.
Wednesday, 30-Jun-2010 14:40:24 EDT
Page Count: 47860
