I also found this document.. Multiple 10g Oracle Home installation - ASM Doc ID: 279353.1 - Karl Arao http://karlarao.wordpress.com On Tue, Aug 11, 2009 at 5:02 AM, sanjeev m<sanjeevorcle@xxxxxxxxx> wrote: > Karl. > > Sorry to respond late as I was not checking this email for few days. > > Thanks for the info. > > - The environment where this is being performed is a non cluster env. > - To start with we installed 10g ASM non-rac home which started ocssd.bin. > At this time all RDBMS instances were on version 10g > - Performed 11g upgrade on one of the SID and to support the upgrade ASM was > upgraded to 11g version as well using localconfig reset OH command. This > caused ocssd.bin daemon to spawn from the 11g OH > - We brought up 11g ASM instance and started all databases to run from 10g > OH. > - My co-dba wanted wanted to bring up(To keep the env in sync with PRD which > is 10gASM OH) the 10gASM instance on a host where the ocssd.bin (running > from) on 11g ASM home. He sources the 10g ASM OH environment and brough up > ASM instance out of that home and was able to mount the diskgroups whilst > the 11g ASM instance was up and running. > > I know that > - ASM Instance at higher version can support both equal and lower version of > RDBMS instance > - You can only start one ocssd.bin process per host from any given version > of ASM software at a time based on where it is configured to start. > I was trying to understand how this setup is working. My guess is the 10g > ASM instance is communicating with the ocssd.bin spawned from 11g ASM HOME. > Basically trying to understand from a conceptual perspective how such setup > is working (supported/unsupported) > > Regards, > Sanjeev. > -- //www.freelists.org/webpage/oracle-l