public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
* [bug?] can't unmount filesystem after running "exportfs -u" -- dangling refcount?
@ 2014-03-21 16:37 Chris Friesen
  0 siblings, 0 replies; only message in thread
From: Chris Friesen @ 2014-03-21 16:37 UTC (permalink / raw)
  To: linux-kernel


I'm seeing some odd behaviour on an NFS server.

We're running 3.4.82 and have a drbd-replicated filesystem 
(active/standby) that is exported via NFS (explicitly v3, and 
/proc/fs/nfsd is mounted).

On a server switchover we take down the NFS server IP address, run 
"exportfs -u" on the exports, unmount the drbd filesystem, and then 
demote drbd from primary to secondary.

The problem we're seeing is that sometimes "exportfs -u" completes 
successfully but "umount" fails with an error that the filesystem is 
busy.  When this happens, "fuser" doesn't see any userspace users, which 
points at the kernel thinking it has a reference open.

When it's in the stuck state, manually running "exportfs -f" seems to 
resolve the issue so that "unmount" can run.

Are there any known issue in this area?

I'm not currently subscribed to the list, so please CC me on replies.

Thanks,
Chris

^ permalink raw reply	[flat|nested] only message in thread

only message in thread, other threads:[~2014-03-21 16:37 UTC | newest]

Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-03-21 16:37 [bug?] can't unmount filesystem after running "exportfs -u" -- dangling refcount? Chris Friesen

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox