Multiple SAP Databases in RAC

[shaun_wimpory2]

Hi everyone,

I am currently exploring SAP Oracle RAC for HA and am wondering if its possible to install multiple SAP Oracle databases into the same RAC cluster?

For example if we had ERP, BW, CRM, SCM ..etc.., is it possible/recommended/supported to migrate their various stand-alone Oracle databases into the same RAC cluster, or should they be migrated into their own RAC clusters?  eg a separate RAC for ERP, RAC for BW, RAC for CRM ..etc.. ??

Pros/cons/challenges ...

We are running SAP/Oracle on AIX (Power) so I have no concerns regarding vertical scalability at this stage.

Regards

Shaun

[former_member188883 · Accepted solution]

Hi Shaun,

Just to extend what Orkun has described , following SAP notes should be able to answer many of your queries.

Note 581320 - FAQ: Oracle Real Application Cluster (RAC)

Note 527843 - Oracle RAC support in the SAP environment

Regards,

Deepak Kori

[shaun_wimpory2 · Accepted solution]

Hi Deepak,

I've read the notes previously and 581320 talks about multiple SAP products running in a MCOD RAC environment, however that is still a single database instance in a RAC cluster.

What I would like confirmation on is the ability to run different/multiple SAP product databases in a single RAC cluster, and how these are administered when everything runs under the same "oracle" account.

Cheers

Shaun

[Former Member · Accepted solution]

Hi, Shaun.

Here is absolutely no issues to run multiple RDBMS homes under the same Oracle Clusterware (i.e. cluster). You can have as many Oracle Database homes as you like. Common thing for all these homes will be Grid Infrastructure, which is not an issue and gives you flexibility maintain multiple RDBMS patch levels. if RAC is used for SAP apps, 527843 forces you to keep RDBMS homes in shared clustered file system (e.g. ACFS), though there is an exception if you're database placed on Oracle's Exadata, this requirement is relaxed and each home can be stored on local storage of database server (http://scn.sap.com/docs/DOC-31409?goback=%2Egmr_4809717).

For separation of administration <SID>adm user is used, but mainly for start/stop/backup database by brbackup, brarchive and brconnect. You are allowed to limit this user to SYSOPER group, which does not have access to data inside the database. Look  at http://www.sdn.sap.com/irj/scn/go/portal/prtroot/docs/library/uuid/9e626b1c-0d01-0010-b2ba-cfa2443c1...  for more information about security.

Additionally you can cluster by the same clusterware your SCS/ASCS, which increases high availability of entire system even more (see http://www.oracle.com/us/solutions/sap/sapctl-303790.pdf).

[former_member188883 · Accepted solution]

Hi Shaun,

Please check if these are useful.

Note 1598594 - BR*Tools configuration for Oracle inst. under "oracle" user

Note 913503 - Collective Note for Oracle 9i RAC

  Sections C, D, and E

Some whitepaper reference

For the most current Oracle white papers concerning the use of RAC in the SAP environment see:

https://www.sdn.sap.com/irj/sdn/ora -> SAP on Oracle Real Application Clusters (RAC)

Regards,

Deepak Kori

[Former Member · Accepted solution]

What OS user will be required for Oracle DB software, Grid Software including ASM and for BRTOOLfor Multiple SAP Databases like ECC, HR , PI and BW.

My confusion is only Oracle user will be sufficient for ASM and each database or separate user ora<sid> is required in this case which user will be used for ASM installation.

[shaun_wimpory2 · Accepted solution]

Hi Usmani,

You use the "oracle" user for the installation of everything Oracle.  orasid is no longer used in this environment.  You use sidadm for specific day-to-day administration (such as brtools etc.)

Cheers

Shaun

[Former Member · Accepted solution]

The current environment is not Oracle RAC and has multiple SID running into it and  each SID has ora<sid> to log on and manage the specific DB and BRTools. No need to set environment everytime when log one to specific sid user to manage DB

However, using one Oracle User for all SID, would you be setting environment variable manually everytime when you log on to Oracle user?

I am still not clear on this. This would be real challenge for us with 7 sid in development environment.

Regards,

Ather

[Former Member · Accepted solution]

Shaun,

Can you please share your experience with only one Oracle user managing multiple SID, how did you configure BRTOOLS and other components.

Ather

[Former Member · Accepted solution]

Heelo !!!

You can use many SAP-Database into RAC enviroment

You can set inside profiles scripts,.. what SID you want to use.,

Do you using wich shell ?

Regards

Sandro Lobo

[Former Member]

Hi Shaun,

It is possible to run over different databases on one RAC. I didn't install multiple homes on RAC from the scratch, but see some SAP installations at my customers. Please find the SAP note about it, below;

Note 1521371 - Oracle 11.2.0: Setting of ORACLE_BASE in SAP environments

Best regards,

Orkun Gedik

[shaun_wimpory2]

Thanks Orkun ... I must admit that running multiple different databases in a RAC cluster raises a heap of questions around how tools such as brtools/brspace/brbackup ..etc.. identify what database is being administered given all the oracle databases, grid, and cluster services run under an "oracle" account vs a "ora<sid>" account.

I'm assuming you run brtools as the "oracle" account also, so how does it know what SID is being "looked" at??

I'm hoping its not a case of manually changing the DB_SID and/or ORACLE_SID environment variables each time.

Cheers

Shaun