We currently have 4 node develpment and 8 node Production RAC environment at our premises. The development currently running on Oracle 10g R2 with patchset 10.2.0.3, which we are planning to upgrade to 10.2.0.4. My god, there are over 20 databases running across these 4 nodes. Uff.. upgrading cluster, asm and all those databases to 10.2.0.4 patchset.. tough time!
Along with upgrade activity, we also plan the following at the same time:
Changing the IPs of public and interconnect on production.
Moving a RAC database from development to production.
Apart from the above, there are couple of small changes to be done.
I know one time such a big change is not recommended and a very tough task too. Thankfully, we are not really into production yet, we have ample of downtime to carry out/complete all these tasks.
Wish me best of luck and I will blog about any issues that I faced during this activity.