Re: A weird autofs problem

[Jim Summers <jsummers@bachman.cs.ou.edu>]

Ian Kent wrote:
> On Thu, 2007-08-16 at 18:44 -0500, Jason L Tibbitts III wrote:
>> I'm trying to debug a very weird problem I've started seeing with
>> autofs over the last couple of days.  The machines I'm seeing this on
>> are all running Fedora Core 5 i386, fully updated (autofs 4.1.4-33 and
>> kernel-smp 2.6.20-1.2320.fc5).  Yes, I'm in the process of rolling out
>> F7, but that will still take at least a couple of weeks and in the
>> meantime I'd like to get to the bottom of this if possible.
>>
>> We use autofs to automount user home directories under /home.  Some
>> users are reporting that their home directories are just disappearing
>> out from under them; attempts to write to them result in "permission
>> denied".  Only once have I seen a system in this state (users keep
>> rebooting the machines) and I don't have a screen capture, but I
>> recall that df showed the user directory as being "there" but showed
>> dashes instead of numbers for the capacity figures.  Unfortunately I
>> don't recall what showed up in the Filesystem column.
> 
> That NFS problem was fixed in 2.6.18 I think.
> 

when i read this, nfs was the first thing that popped into my mind also. 
second would be a network outage.  i have experienced the exact symptoms, but 
on static nfs mounts, after i have brought down the server for extended 
periods, or the net is out for long periods, then a client will do this.  i 
simply recover by umounting then doing a mount -a.

hth



>> I can't think of anything which has changed on the affected systems.
>> Since they're running FC5 nothing is getting updated.  The automount
>> maps are served via LDAP and as far as I can tell the queries aren't
>> failing.  The server doesn't report any problems.  Nothing has changed
>> recently on either the LDAP servers or the NFS servers.
> 
> Something has changed?
> 
>> So I'm at a complete loss here.  If I can access a system while the
>> problem is manifesting I'm sure I can find some more useful
>> information but until then I was hoping that either someone might have
>> seen something liks this and had an idea of what might be causing it
>> or someone might have some idea of how I might go about debugging
>> this.  I have debugging turned on but haven't seen anything useful
>> yet.
> 
> We'll need you to get a first hand look at a broken system and have a
> look around and see what really is wrong. And you know that a debug log
> would be good too.
> 
> Ian
> 
> 
> _______________________________________________
> autofs mailing list
> autofs@linux.kernel.org
> http://linux.kernel.org/mailman/listinfo/autofs

-- 
Jim Summers
School of Computer Science-University of Oklahoma
-------------------------------------------------