Re: How to avoid rebooting Linux NFS-client when NFS-server is not available?

From: Peter Funk <pf@artcom-gmbh.de>
To: Dick Streefland <dick.streefland@altium.nl>
Cc: linux-nfs@vger.kernel.org
Subject: Re: How to avoid rebooting Linux NFS-client when NFS-server is not available?
Date: Fri, 26 Jul 2013 14:08:49 +0200	[thread overview]
Message-ID: <20130726120849.GA12584@pfmaster> (raw)
In-Reply-To: <6f01.51efd09f.c2ac3@altium.nl>

Dick Streefland wrote 24.07.2013 13:03:
> Peter Funk <pf@artcom-gmbh.de> wrote:
> | We've researched this question for quite a while now and nobody here
> | found a solution to the following problem:
> | 
> |  1: A Linux computer is NFS client of some other Linux NFS server
> |     and has some active mounts and some processes working with files 
> |     on that NFS server.  
> | 
> |  2: Now the NFS server becomes unavailable and a system administrator 
> |     wants to clean up the situation on the NFS client computer without 
> |     having to reboot this client computer.
> | 
> | Is this possible?  And if how exactly?
> 
> What you could try is temporarily add the IP number of the dead NFS
> server to another NFS server. The other NFS server should reject any
> request for the dead mount, and the client can continue with an error.

Indeed: This workaround seems to work!

Assume example: The NFS-server has IP 192.168.123.45 and the client
has also the nfs-kernel-server package installed and it is running.
Then this sequence on the client did the trick::

    ifconfig eth0:fakesrv 192.168.123.45 up
    umount -f -l ....
    umount -f -l ....
    ....
    ifconfig eth0:fakesrv down

Best Regards and many thanks for your suggestion,
Peter Funk
-- 
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