umount filesystems crach...

[Bob Jones]

On Thu, 29 Jan 2004 12:58:14 +0100 (CET), MG <makgab at freemail.hu> wrote:
>
> Sometimes when I shutdown the system, then crach the linux. I have to 
> reset the
> machine. :(
> The shutdown process freezes at umount filesystems. Why?
>
This happened to me also. 'Took a while to figure it out. I'm running a 
dual PIII 450 on an old 440GX motherboard, 2940U2W Adaptec SCSI card and 
FC1-testing, fully updated. Although it doesn't make any difference if you 
are running "testing" or "base" right off of the CDs. It only occurs when 
running the nptlsmp kernels and NFS, not the plain uni-processor (nptl) 
kernels - NFS or not. If you're not running smp kernels ignore this. It's 
not the same problem.

What I found was that, if there is just one system/directory listed in the 
/etc/exports file that does not have its internet address listed in the 
/etc/host file, the system will hang - just as yours did. I was lazy and 
copied the files from othe machines on the network without paying 
attention to the inconsistancies. The tip-off to the problem shows up in 
the /var/log/messages file  "exportfs: foo has non-inet addr". And that's 
all that shows up in the logs. I'm convinced that this also causes the 
mysterious hangs at undetermined intervals when just running without 
re-booting. In happened to me twice - but I re-boot frequently on my 
"testing" machine. Ultimately, if you let this go on after several reboots 
you'll corrupt the root file system. I initially attributed the problem to 
an old SCSI drive that I was using on my "testing" machine - but it still 
occurred after installing a new drive. Interestingly, the last time I got 
to the point of having to do a forced fsck I rebooted and appended 
autofs=off to the command line and booted up cleanly. Moreover, if you 
turn off/stop autofs in "System-Services". the hangs do not occur,

HTH

Bob Jones