Re: Unmount a busy NFS share

[hendrik@topoi.pooq.com]

On Sun, Jun 18, 2006 at 01:36:33PM +0200, Frank Blendinger wrote:
> On Sun, Jun 18, 2006 at 12:43:51PM +0200, Bernd Schubert wrote:
> > Frank Blendinger wrote:
> > > I want to unmount a busy NFS share, but failed to do so, even with a
> > > umount -f.
> > 
> > [...]
> > 
> > > I also tried a ``fuser /mothermole'' to see which process blocks the
> > > mountpoint, but that just hangs, I aborted after some minutes. I'm
> > 
> > Just try 'lsof |grep mothermole'.
> 
> This hangs, just as my try with fuser did.
> 
> That b0rked up NFS mount seems to cause a lot of trouble, i.e. updatedb
> processes from the last view days are hanging around, blocked, and also
> some other programs refuse to start as the try to access that
> mountpoint.
> 
> Is there really no other way then rebooting to get rid of this nasty
> thing?

There really ought to be, shouldn't there?  What is it that reboot does
to unmount the file system that we can't?

Well, actually, .... I find that reboot sometimes does no better.  *it* 
hangs during shutdown when trying to unmount NFS volumes.  Then I have 
to use a hardware reset to accomplish a reboot.  And it ends up spending 
an age fscking and recalculating quotas.  In its doomed attampt to make 
sure everything is shut down properly, it ends up making more damage 
necessary.

I get this problem when the NFS server goes down and the clients are 
still active.  Really, they shouldn't wait forever.  Since my server is 
an AMD-64 with nvidia-driver instability, this happens way too often.

I've noticed that if the NFS server goes down and is rebooted everything 
is fine, provided none of the clients do *anything at all* to it while 
it is down.  But if they try to do anything at all woth the NFS-mounted 
system, eve, unmount it, they hang forever.

-- hendrik

> 
> 
> Greetings,
> Frank
> 
> -- 
> Frank Blendinger | fb(at)intoxicatedmind.net | GPG: 0x0BF2FE7A
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