I actually just ran into a problem like this between 2 NetBSD 2.0 (i386) 
systems today... NFS over UDP, where client accesses just started 
hanging until I rebooted the client.  (although, "shutdown -r now" did 
successfully reboot for me).

My processes weren't zombies; ps showed them in disk wait;  all other 
network traffic seemed OK, but NFS just died.  (after some days of being 
fine, and it's fine again after client reboot)

+j

Christos Zoulas wrote:

>In article <20050104192819.M8836@welmers.net>,
>Bastiaan Welmers <haasje@welmers.net> wrote:
>  
>
>>Hi,  
>> 
>>I'm experiencing very annoying NFS problems with NetBSD.  
>> 
>>It happens often that a mounted NFS share just breaks down, for a reason  
>>that I cannot understand, because the connection is still up, I can ping,  
>>ftp, telnet whatever between the two computers, but the NFS connection went  
>>completely dead. Every process using the share turns into a zombie and can't  
>>even be killed. umount -f does not work (and turns into a non-killable  
>>zombie). Only solution is to hard-reboot the computer (can't even be  
>>rebooted by the "reboot" commando, just hangs at the shutdown scripts).  
>> 
>>Another day the nfs share works without problems.  
>> 
>>Is there something that can be done to avoid this (in particular the 
>>aggravating zombie behavior) ? I tried  
>>something with time-out values but the error still returns.  
>> 
>>This happens between two netbsd boxes, versions 1.6, 2.0 every combination.  
>> 
>>    
>>
>
>Is that NFS over tcp or udp?
>
>christos
>  
>


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Jeff Rizzo                                         riz@redcrowgroup.com
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