[UPDATE] Re: FreeBSD NFS server not responding to TCP SYN packets from Linux/SunOS clients

[Heinrich Rebehn]

Nicolas KOWALSKI wrote:
> On Fri, 14 Oct 2005, Nicolas KOWALSKI wrote:
> 
> 
>>Mike Silbersack <silby at silby.com> writes:
> 
> 
>>>Actually, there may be a quick fix for this specific machine.  If 
>>>you set net.inet.tcp.keepidle to 1 minute (60*whatever kern.hz is), 
>>>that'll cause keepalive packets to be sent every minute to an idle 
>>>connection, rather than every 2 hours.  That would kill the stuck 
>>>connections much quicker.
>>
>>Unfortunately, this does not work as expected. I just tested with my 
>>workstation (Linux 2.6), with NFS filesystems mounted with TCP; when 
>>the station rebooted abruptely, mounting the same NFS filesystems hung 
>>more than 1 minute (15 minutes just now). During this hang, I saw on 
>>the server, using netstat, the nfsd process related to my workstation 
>>in ESTABLISHED state.
> 
> 
> Thanks to Olivier, his suggestion to restart the nfsd processes after 
> setting net.inet.tcp.keepidle makes the situation much better !
> 
> Now, this work as expected ; Linux and SunOS workstations do not hang 
> more than a few seconds when mounting shares from the FreeBSD server 
> after an unclean shutdown. I am still waiting for other problems to come 
> up with this configuration, but after a few hours, it just looks really 
> good. :-)
> 
> Many thanks to all !
> 
> Best regards,

Great news. I will give that a try.
Still, i wonder if it is possible to have the server close the open
connections with a small program that one could call before the first
mount. Can someone give me a hint?

--Heinrich


-- 

Heinrich Rebehn

University of Bremen
Physics / Electrical and Electronics Engineering
- Department of Telecommunications -

Phone : +49/421/218-4664
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