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

[Nicolas KOWALSKI]

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,
-- 
Nicolas