CentOS - Oct 2009 - NFS lockups

I thought this had been fixed with newer kernels?
We have an old Maxtor Snap Server, an 80 GB NAS unit, containing some of our
archives.
Both of our CentOS servers have it permanently mounted by NFS for convenient
access.
This weekend, I discovered remotely that, although all systems except the
VRTSralus remote agents for Veritas (now Symantec) Backup Exec were working just
fine, both servers would freeze a shell solid on starting to run
"lsof" or half way through a "df". However,
"mount" ran OK and showed the next item in the "df" should
have been the Snap Server NFS mount. I pinged it and it did not respond -
I'll let you know Monday what is up. "umount -f"  showed
"Device busy" but "umount -l" worked just fine and
"df" "lsof" and "VRTSralus" all work OK now. BTW
the Veritas does not access the Snap Server, though the weekly cron-job to
tar-ball the Snap Server at 02:00 Saturday did not email me at all, though it is
shown in /var/log/cron.

Does anyone know of a method to make NFS mounts auto un-mount if the remote
server disappears?


Mike Yates    MBCS CITP (ISSG)
IT Support Engineer

Hawkgrove Ltd  -  Software Systems Design
2, The Business Courtyard, Marl Pits Lane, Trudoxhill, Frome, Somerset, BA11
5DL, UK
+44 (0)1373 837900     fax:  +44 (0)8700 518155
Registered in England: 2756481  VAT Reg: UK 601 1137 11
Registered Office: NSO Associates LLP, 75 Springfield Road, Chelmsford, Essex
CM2 6JB
All e-mail is subject to contract and is not intended to create a legally
binding agreement.
Hawkgrove Ltd will only be bound by an agreement in writing signed by an
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03:45:19 2009 Known viruses: 625330.

Regarding automount, have you tried autofs?

I'm not a fan of static mounts via fstab.

We've a flaky server and I set my timeout in auto.master for 60  
seconds for NFS servers and about 30 seconds for USB/FW drives.



On Oct 3, 2009, at 6:56 AM, Mike Yates wrote:
> I thought this had been fixed with newer kernels?
> We have an old Maxtor Snap Server, an 80 GB NAS unit, containing  
> some of our archives.
> Both of our CentOS servers have it permanently mounted by NFS for  
> convenient access.
> This weekend, I discovered remotely that, although all systems  
> except the VRTSralus remote agents for Veritas (now Symantec) Backup  
> Exec were working just fine, both servers would freeze a shell solid  
> on starting to run "lsof" or half way through a "df".
However,
> "mount" ran OK and showed the next item in the "df"
should have been
> the Snap Server NFS mount. I pinged it and it did not respond - I'll  
> let you know Monday what is up. "umount -f"  showed "Device
busy"
> but "umount -l" worked just fine and "df"
"lsof" and "VRTSralus" all
> work OK now. BTW the Veritas does not access the Snap Server, though  
> the weekly cron-job to tar-ball the Snap Server at 02:00 Saturday  
> did not email me at all, though it is shown in /var/log/cron.
>
> Does anyone know of a method to make NFS mounts auto un-mount if the  
> remote server disappears?
>
>
> Mike Yates    MBCS CITP (ISSG)
> IT Support Engineer
>
> Hawkgrove Ltd  -  Software Systems Design
> 2, The Business Courtyard, Marl Pits Lane, Trudoxhill, Frome,  
> Somerset, BA11 5DL, UK
> +44 (0)1373 837900     fax:  +44 (0)8700 518155
> Registered in England: 2756481  VAT Reg: UK 601 1137 11
> Registered Office: NSO Associates LLP, 75 Springfield Road,  
> Chelmsford, Essex CM2 6JB
> All e-mail is subject to contract and is not intended to create a  
> legally binding agreement.
> Hawkgrove Ltd will only be bound by an agreement in writing signed  
> by an authorized signatory.
> All outgoing email is scanned by Kerio, using ClamAV 0.94.2/9865/Sat  
> Oct  3 03:45:19 2009 Known viruses: 625330.
>
> _______________________________________________
> CentOS mailing list
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