Using VCS Failover to Upgrade Group Components!

This, like many of my posts, may be old hat to some folks, but here's a little something for those of you who might find it of interest.We'll assume we have two systems (systema and systemb) each with the ability to run one or more of 4 service groups (grpa, grpb, grpc and grpd) and their related services. For this example's sake, systema is running grpa and grpb and systemb is running grpc and grpd.So now, both machines (systema and systemb) need to have a patch installed, or something like that, and you can't afford for your product to go down. With Veritas Cluster HA failover (VCS), it's a pretty simple thing to do (now, we're assuming everything goes well, of course ;)Since we're going to upgrade systema first, we need to move all the services over to systemb. You have, basically, two options here (at minimum) since you want to move everything off. Either (from systema):

hagrp -switch grpa -to systemb
hagrp -switch grpb -to systemb
or
hagrp -offline grpa -sys systemb
hagrp -offline grpb -sys systemb

The second option (using "-offline") means that you'll need to online the service groups on systemb if they don't fail over automatically

hagrp -online grpa -sys systemb
hagrp -online grpb -sys systemb

To make sure it sticks during your work (i.e. in case Veritas gets smart and decides that systema is okay and tries to move the service groups back!)

From systema:
hagrp -freeze grpa
hagrp -freeze grpb

You can use the "-persistent" flag on the freeze, if you need it to be down after reboot (e.g. hagrp -freeze grpa -persistent)You basically do the same thing in reverse to get stuff back to normal, and then switch all the service groups to systema so you can upgrade systemb. There are other options to make things go faster, but it all gets a little complicated and long-winded at some point