For IBM CMOD Upgrades, if you're going to take an outage, you do everything that needs to be done at once. If you have different teams, you have the OS upgraded first, then the DBAs and CMOD Admins can work in parallel after the system comes back up.
-JD.
I've done this two different ways.
Process One1) We did AIX/DB2/CMOD on different weekends, this took a while because we had numerous tiers, but it was a very large system, for from what i understand was one of the "top 20" largest customers of CMOD.
One weekend- AIX
Test for a month, verify stability
One weekend - DB2
Test for a month, verify stability
One weekend - CMOD (Backup site)
Test for a month, point all users to this backup site
One weekend - CMOD (Primary site)
ONCE EVERYTHING WAS VERIFIEDProcess TwoOver a Weekend.
1) SA's did AIX upgrade / patches , quick verification. DBA's hopped in, upgraded/patched DB2, quick verification, Then they gave us CMOD...then we did some loads/testing. And that was really it. It was a very very small system.. < 1TB of cache. From my knowledge, system is still stable.