Adding a VG or extend it in HACMP

[LeDam]

Hello,
Here is my question:
I have an HACMP AIX cluster with 2 unused shared disk. We want to migrate a filesystem to this 2 disks.
We have two possibilities :
- Create a new VG and migrate this FS on this new VG
- extend the existing VG and migrate the LV on this two PV.

My question is :
if i create a new VG (for my client, this is a better solution), i think i have to resynch HACMP (so i need to stop it)? Is it true?
in the second solution, we doesn't need to stop HACMP? A simple varyonvg -b -u and then import is enough ?
Thanks for helping me...

 

[denalibird]

It really all depends. Are you using classic or ES and what version?

 

[nabob1]

You have to resync the cluster every time you change, add or remove things from the clustered environment, before you synch, be sure to do a verification; during this stage you will be able to fix any lurking problem.

Also take a snapshot of the cluster before you start to modify things, you can back out with the snapshot by replacing things to the way it was before, be very careful if you are not sure of what to do, it may come back to haunt you in a very big way, good luck.

 

[denalibird]

You do not have to stop HACMP in order to make the changes you suggest.

You are right about the varyonvg -bu vgname from the primary node, on the secondary node you will need importvg -L vgname. If you do it this manual way.... be sure to go back to your primary node, and issue a varyonvg vgname. (no flags)

Once your changes are made, you should sync your topology and then resources in this order.

 

[LeDam]

So if i add a new shared VG, i haven't to stop HACMP?

 

[denalibird]

This is true for HACMP/ES. Classic HA is a different story.

You can verify this is in your HACMP Administration's Guide.