I've this error on my installation. drbd and heartbead are installed both side. Any ideas?

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Last updated: Tue Oct 12 22:00:02 2010
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Stack: Heartbeat
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Current DC: ha2 (8de4b285-24ef-4d59-9417-e7a137584e3a) - partition with quorum
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Version: 1.0.8-042548a451fce8400660f6031f4da6f0223dd5dd
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2 Nodes configured, 1 expected votes
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2 Resources configured.
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Online: [ ha1 ha2 ]
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Resource Group: WebServices
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fs_webfs (ocf::heartbeat:Filesystem): Started ha1
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Master/Slave Set: ms_drbd_webfs
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drbd_webfs:1 (ocf::linbit:drbd): Slave ha2 (unmanaged) FAILED
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Masters: [ ha1 ]
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Failed actions:
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drbd_webfs:1_start_0 (node=ha2, call=4, rc=5, status=complete): not installed
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drbd_webfs:1_stop_0 (node=ha2, call=7, rc=5, status=complete): not installed

I apologize that this post won't be very helpful in terms of addressing your problem, but I have used Heartbeat+DRBD+NFS in the past and based on my experience it is absolutely not worth the trouble.

You can create some really sophisticated setups to failover, and sometimes it works. But a lot of the times the failover process for me got stuck because of open files or some other reason and getting it unstuck was a huge pain. Heartbeat v2 supposedly added some great features, but in practice (at least for me) it added a lot of needless complexity, and the documentation is horribly lacking.

Best of luck getting it working. Perhaps I just didn't have something setup correctly, or maybe there have been improvements since two years ago when I was using it, but that was just my experience FWIW

A qualified guess would be that your volume is not in a safe state or that it for some reason cannot be unmounted.

Check /proc/drbd on both machines. Also dump your pacemaker configuration (crm configure)

If you're playing with dual primaries you should really look into a filesystem with distributed locking mechanisms, like GFS+ or OCFS2. I prefer the latter one, for no apparent reason!