Oracle RAC for SAP on Linux and OCFS

[Former Member]

We are going to be installing SAP with Oracle 10.2.0.4 RAC on Linux RHEL 5.2 and OCFS. The Oracle RAC documentation states:

You must store the following components in the cluster file system when you use RAC

in the SAP environment:

- Oracle Clusterware (CRS) Home

- Oracle RDBMS Home

- SAP Home (also /sapmnt)

- Voting Disks

- OCR

- Database

I'm curious about the requirement of installing the Oracle Home on shared clustered filesystem. In other RAC installations I've built, I installed the binaries on local filesystems on each node. This is to facilitate the concept of rolling patches. With the SAP's requirement, it appears rolling patches are out of the question. Can someone enlighten me on why SAP requires the Oracle Home reside on shared filesystem.

Thanks

[Former Member]

Hi

You have to place ORACLE_HOMEs on shared cluster file system since they have to be accessed by all RAC instances since SAP insists on having only one shared Oracle Home for all database instances. This means no rolling upgrade and that's way you have to shutdown all RAC instances once you want to apply Oracle patches

regards

Abdel

[Former Member]

We have even put /oracle/SID on OCFS, because the brtools cannot cope with local FS. If you take a backup on node1, then you cannot restore it from node2. Or you could start multiple brconnects at the same time (this is normally prevented with a lock file). Of course you could run all your all your br commands on a dedicated node, but this doesn't fit the RAC idea much.

Just my two cents, of course this does not fully explain, why the ORACLE_HOME has to be shared as well.

Best regards, Michael

Edit: Ahh, now i recall, i really think it is because of the BR*Tools, they need the initSID.sap file in ORACLE_HOME/dbs. This implies that it won't be a big thing to get SAP on RAC running with local ORACLE_HOME's, but that doesn't help a lot as long as SAP does not officially support it...