creating a volume group when using clusters

[Jeff_Traigle]

That must be where I was remembering it from... the NFS module of the Serviceguard class. Whether required or not, it does make your administrative life much easier if you keep as much as possible symmetrical between the nodes as possible.

[TwoProc]

John,

I've found life a lot easier if I make sure that the group numbers are unique across all servers in the cluster. And, I do it for ALL vg's in all of the clustered servers. True enough, you don't HAVE TO. But, you'll certainly avoid any chance of problems later on. I do not apply that rule for root (vg00) on both servers, but you can extend that to any vg's comprised of local disks that won't be moving with the package.

At a minimum, the vg's group number needs to be unique for all clustered vg's in the cluster.

So, if you've got disks that are moving between machines, then those numbers should be unique between all the machines, and not collide with ANY vg's group numbers (local or not) on all of the machines in the cluster.

Which I just simplify to the sysadmin's in our group by saying "all vg's group numbers are unique across the WHOLE SAN" - which is an over-the-top way to avoid any problems down the line, but I do it anyway.

[John Jimenez]

Thanks guys. Yes I would prefer to keep it the same too. Thanks for clearing that up for me.