Re: autofs not mounting from nis maps

[David <spoel@xray.bmc.uu.se>]

On Wed, 2005-03-16 at 15:31 -0800, Jim Carter wrote:
> On Wed, 16 Mar 2005, David wrote:
> > [root@appel2 proc]# ypcat -k auto.master
> > /home  auto.home
> --- snip ---
> > [root@appel2 proc]# ypcat -k auto.home | head -8
> > magnusa  hirst:/homes/hirst/dsk1/&
> 
> We do almost exactly the same thing, except our auto.home map includes the
> full path name, i.e.
> 	prob-mp sonia:/h1/guest/prob-mp
> rather than using the &.  But I'm sure this is not your problem.  I 
> explicitly specify the map type in /etc/auto.master, i.e. 
> 	/home           yp:auto.home
> but again, I doubt that has anything to do with your problem.

Neither of these helped, and indeed nothing I found on the net seemed to
have any impact.

> 
> We're using autofs-4.1.3; what version are you using?  
4.1.2 and 4.1.3 depending on Fedora installation.

> 
> Since automounting works perfectly if it's a file map, I'm inclined to 
> blame YP and not look at either NFS mounting or autofs.  (Do log files 
> suggest that I'm wrong here?)
Log files say hardly anything, even when automaount is started with -v
and or -d.

My guess is that autofs misinterprets the YP maps in some way. Could it
be something with spaces versus tabs in the map files?


> 
> Is it always the same users whose homedirs fail to mount?  Or will Mangusa 
> mount one day and not the next?  Do all the workstations behave equally?  I 
> assume both servers have some failing users.  Does the failure rate vary 
> with the time of day or with obvious system activities like backups?  I 
> know that our YP wierds out at 2 AM when the backups kick off, because the 
> network is overloaded.

No it's consistently the same failure and also for different autofs
versions. The auto.home map contains little over 100 entries with 10

> 
> YP relies on UDP.  If there were network problems that ate YP packets 
> intermittently, it would explain the problem.  If a workstation pings the 
> YP server host (at a time of day when automount failures are seen), what's 
> the packet loss rate?  Is there any other reason to suspect flakiness in 
> the YP server and/or client?  Suppose you do "ypmatch $user auto.home", 
> iterating over and over through all your users, do you see any failures?
> (We don't, except during backups.)
The following simple script showed me that 57 out of 105 entries in the
auto.home file actually are not matched, indicating that this is indeed
a YP problem. Are there some cached YP files somewhere? Restarting yp
did not help.

#!/bin/csh -f

foreach user ( `ypcat -k auto.home | awk '{ print $1 }'` )
  ypmatch -k $user auto.home
end


-- 
David.
________________________________________________________________________
David van der Spoel, PhD, Assoc. Prof., Molecular Biophysics group,
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596,          75124 Uppsala, Sweden
phone:  46 18 471 4205          fax: 46 18 511 755
spoel@xray.bmc.uu.se    spoel@gromacs.org   http://xray.bmc.uu.se/~spoel
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