CRS and Voting Disk

[aunshakeel]

Greeting Friends,
I have recently been given a task to install 11g RAC release 2 on two brand new IBM p7 servers using AIX 7.1 with ASM.
I have to provide a list of pre-requisites that the IBM vendors can provide me while doing their part of OS installation.
I have not installed RAC environment before and i am sure it is not similar to installing 11g on single node with normal filesystem.
In the pre-requisites i have to ask them to give me space for ASM, Voting disks and CRS.
I dont know if the same raw disk can be utilised for all three or should i request them separately.
also i want to know what is the recommended space requirements for setting up CRS and Voting Disks.
any help would be appreciated.

[Tim...]

Hi.

The prerequisites are listed in the AIX installation manuals. See:

http://docs.oracle.com/cd/E11882_01/ins ... 14/toc.htm
http://docs.oracle.com/cd/E11882_01/ins ... 60/toc.htm
http://docs.oracle.com/cd/E11882_01/ins ... 32/toc.htm

As far as ASM setup, Oracle provide very few recommendations:

http://docs.oracle.com/cd/E11882_01/ins ... m#CHDJBEDC

There are a range of ways you can set things up and all are supported. The ASM manual has some very basic recommendations, listed here:

http://www.oracle-base.com/articles/10g ... isk_groups

They are:

- In most cases you will only need two disk groups (DATA and FRA), where DATA holds all database related files and FRA holds the fast recovery area, including multiplexed copies on online redo logs and controlfiles. Typically, the FRA disk group will be twice the size of the DATA disk group, since it must hold all backups.
- Oracle recommend a minimum of 4 LUNs per disk group, with LUNs using hardware RAID and external redundancy if possible.
- All LUNs within a disk group should be the same size and have the same performance characteristics.
- LUNs should be made up from disks dedicated to Oracle, not shared with other applications.

Some people put the voting disk and ocr into a small additional disk group (makeing 3 disk groups in total), but you don't have to.

Cheers

Tim...

[aunshakeel]

Thank you for the reply Mr. Tim

[Tim...]