Oracle RAC – Clusterware Installation Overview

This post covers overview of Oracle Clusterware Installation, for step by step guide on How to install Clusterware using VMware 2.0 (including steps to configuring multiple linux machine/network card/hard disk/raw device for OCR/Voting Disk on one Windows Machine)  register for online Oracle RAC DBA training (499 USD)


Requirement for Oracle Clusterware

1. External Shared Disk to store Oracle Clusterware file (Voting Disk and Oracle Cluster RegistryOCR)  To know more about OCR & Voting Disk click here

2. Two netwrok cards on each clusterware node (and three set of IP address) –
Network Card 1 (with IP address set 1) for public network
Network Card 2 (with IP address set 2) for private network (for inter node communication between rac nodes used by clusterware and rac database)

IP address set 3 for Virtual IP (VIP) (used as Virtual IP address for client connection and for connection failover)

3. Storage Option for OCR and Voting Disk – RAW, OCFS2 (Oracle Cluster File System), NFS, …..

Preinstall Steps/Check

Create group and user for clusterware installation (for ex. oracle:dba) on all nodes

2. Configure ssh on all nodes so that oracle user on one node can login to other nodes without password prompt (In Oracle Clusterware/RAC terminology this is called as User Equivalency)

3. Configure Network card (public and private network) and ensure that all nodes can ping each other on public & private nodes.
Ensure that VIP (Virtual IP) is not in use by any system on network including cluster nodes .

4. Ensure all O.S. packages (RPMs) are installed on system as mentioned in installation Guide (for ease select all RPM’s during O.S. installation)

5. Ensure that directory for voting disk and OCR are shared on all nodes of RAC.
 OCR should be owned by root:dba where as Voting Disk should be owned by oracle:dba

6. Create Oracle Clusterware Home Directory (Clusterware HOME a.k.a. $CRS_HOME) on all nodes and change owner as oracle:dba  (This could be on shared/nonshared (local) storage)

7. Run Cluster Verification Utility (Utility to check system prerequisites for clusterware, rac db installation)

/mountpoint/crs/Disk1/cluvfy/ stage -pre crsinst -n node_list   (It is safe to ignore issues related to packages/rpms and VIPCA)

338924.1  CLUVFY Fails With Error: Could not find a suitable set of interfaces for VIPs

Clusterware Installation

1. Start Clusterware installation using ./runInstaller

2. Specify Clusterware Home (directory created on step 6 above – preinstall checks)

3. Specify Cluster Nodes – node1, node2

4. Specify location of Voting Disk & OCR (step 5/6 in preinstall steps)

5. Click on Install

6. Run on all nodes when prompted ( will call rootinstall & rootconfig explained below)

While running on last node, If you see error message like – “The given interface(s), “eth0” is not public. Public interfaces should be used to configure virtual IPs

run vipca (from $CRS_HOME/bin as root user)

7. Return to clusterware installation screen and click OK , Installer will automatically configure ONS, Private Interconnect ($CRS_HOME/cfgtoollogs/configToolAllCommands)

8. Finally you should see successful clusterware installation screen.

Oracle Clusterware Installation Stages (what goes in the background)

There are three stages of Oracle RAC clusterware installation

A. Stage 1

In this stage you provide –
a) CRS Home details (Directory to install clusterware)
b) Provide VIP, PRIC and Public node details
c) Location of voting disk and OCR

Installer copies Clusterware software (binaries) for CRS Home

B. Stage 2

In this stage Installer prompts you to run as root user on all nodes – This script calls rootinstall & rootconfig from CRS_HOME/install directory

rootconfig – This is important script which does following task (plus some additional task)
– Creates the directory structure for scls_scr in /etc/oracle (Linux) or /var/opt/oracle (Solaris)
– Populates the ocr.loc file  in above directory
– Creates the log directories for the clusterware daemons in CRS_HOME/logs
– Initialize OCR (Oracle Cluster Registry) device for cluster configuration details
– Setup OCR (Oracle Cluster Registry) to run CRS (Cluster Ready Service), CSS (Cluster Synchronization Service)
– Copy the CRS init script to init.d for init process to start at boot time
– Add entry in /etc/inittab file and set the appropriate links in /etc/rc.d/rc*.d folder
– Start the CRS stack 
– calls VIPCA to configure Virtual IP address for each node
– Configure NodeApps if CRS is up and running on all nodes

C. Stage 3

In this stage installer runs $CRS_HOME/cfgtoollogs/configToolAllCommands


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About the Author Atul Kumar

Oracle ACE, Author, Speaker and Founder of K21 Technologies & K21 Academy : Specialising in Design, Implement, and Trainings.

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Leave a Comment:

aashok says September 20, 2009

This is really a very good consolidate doc.

Keep healthy posting.

Kunal says March 4, 2010

Hey, BTW did u try out this exercise? In my case, the process is unable to create CRS, because Cluster ID mismatch. I tried it several times but everytime cluster configuration if failing, though i meet all the criterias. The point to be mentioned here is i had created OCR on .VMDK file.

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