[Pacemaker] Correct order for expanding OCFS2 filesystem?

[Mark Komarinski]

This issue touches a number of different places, but I got a working 
environment from the Dual Primary DRBD + OCFS2 HOWTO, so I hope there's 
enough expertise here to answer my question.  Background on these 
systems is Debian Squeeze, nothing from backports, configuration mostly 
from the above listed HOWTO.

I've been able to (mostly) successfully build a Pacemaker-based 
LVM/DRBD/OCFS2 filesystem shared between two hosts.  Among the sticking 
points so far is how I can successfully extend the filesystem when it 
starts getting close to its limit.

In the past when we were active/passive, the process was:

- lvextend the underlying DRBD partitions
- drbdadmin resize the drbd device
- extend the ext3 filesystem

With OCFS2 (or active/active?) this appears to be more complicated.  The 
DRBD documentation says that you have to be active/passive in order for 
online extensions to work.

This then implies the process is:

- lvextend DRBD
- shut down one side (stop corosync and start just drbd and make it 
secondary)?
- drbdadmin resize the drbd device on the active side
- tune.ocfs2 -S on the active side
- stop drbd and restart corosync on the passive side
- profit?

Since this is backing a TWiki install, taking one server offline 
temporarily to do this isn't a problem, but I'm not able to get this to 
work, and often requires reboots of both systems and eventually the new 
extended size is seen by ocfs2.

-Mark

-- 
Mark Komarinski				mark_komarinski at hms.harvard.edu
Manager					http://ritg.med.harvard.edu
Research IT Group
Harvard Medical School