3 Replies Latest reply: Oct 10, 2012 9:16 AM by user8684352 RSS

    RAC with different db versions

    user8684352
      Hi all,

      we are planning to have several db in a new environment. One question to be solved is how to achieve highest degree of availability for all db.

      QUESTION:
      Can I have a RAC environment with different db versions running in this environment? In this case it could be different releases of version 10 and/or different base releases (version 10 and version 11).
      Whcih version is needed for ASM and Clusterware?
      Are there any restrictions as to the operating system? etc.
      Where can I find information about this? Are any documents, white papers ... available?
      Up to now we do not know what machines and operating system we will use; possible candidates are SOLARIS or LINUX.

      Does anyone have experiencew with this?
      Any help is appreciated.
        • 1. Re: RAC with different db versions
          Sebastian Solbach -Dba Community-Oracle
          Hi,

          => Yes you can have multiple versions of RDBMS. For each RDBMS version you will need a separate ORACLE_HOME.
          => You can only have one version of ASM and clusterware, and they should (ASM) and must (OCW) be the newest in the stack.

          See the following MOS notes for more information:

          -> Oracle Clusterware - ASM - Database Version Compatibility (Doc ID 337737.1)
          -> Pre 11.2 Database Issues in 11gR2 Grid Infrastructure Environment (Doc ID 948456.1)

          Also make sure you use the correct ASM compatibility level in your diskgroup to support the correct DB versions and have new ASM functionalities enables:
          http://docs.oracle.com/cd/E11882_01/server.112/e18951/asmdiskgrps.htm#CHDDIGBJ

          There are no restrictions on OS other than the depending requirement for each release.
          You may hit the limit though for example if you want to use RHEL6. 11.2.0.3 is certified, 10.2.0.2 not, hence you will not be able to use RHEL6 for 10.2 and 11.2.

          So you should first check which Linux/Solaris version is generally supported. You probably are safe if using the latest OL 5 and Solaris 10.

          Regards
          Sebastian
          • 2. Re: RAC with different db versions
            Balazs Papp
            yes you can

            Grid Infrastructure (ASM, clusterware) version must be always higher or equal than the highest database version in the cluster
            you can have different versions/database running on the same cluster (but instances at the nodes for the same database of course must be at same version)

            if you want to run 10g databases, you should choose Oracle Linux 5.8 or Solaris 10 as operating system (OL 6/Solaris 11 is supported only starting with 11.2.0.3)
            • 3. Re: RAC with different db versions
              user8684352
              Hi all,

              thank's for your help.

              FJH