[CentOS] how to unmount an NFS share when the NFS server is unavailable?

Thu Jan 27 06:57:30 UTC 2011
Rudi Ahlers <Rudi at SoftDux.com>

On Thu, Jan 27, 2011 at 1:26 AM, Les Mikesell <lesmikesell at gmail.com> wrote:
> On 1/26/2011 4:55 PM, Dr. Ed Morbius wrote:
>>
>> The specific solution is 'umount -fl<dir|device>'.
>>
>> The general solution's a little stickier.
>>
>> I'd suggest the automount route as well (you're only open to NFS issues
>> while the filesystem is mounted), but you then have to maintain
>> automount maps and run the risk of issues with the automounter (I've
>> seen large production environments in which the OOM killer would
>> arbitrarily select processes to kill ....).
>>
>> Monitoring of client and server NFS processes helps.  If it's the filer
>> heads which are failing, and need warrants it, look into HA failover
>> options.
>>
>> Soft mounts as mentioned won't hange processes, but may result in data
>> loss.  This is most critical in database operations (where atomicity is
>> assumed and generally assured by the DBMS).  If the issue is one of
>> re-running a backup job, and you can get a clear failure, risk would be
>> generally mitigated.
>
> Actually, since the original question involved access to backups, I
> should have given my usual answer which is that backuppc is the thing to
> use for backups and it provides a web interface for restores (you pick
> the historical version you want and either tell it to put it back to the
> original host or you can download a tarball through the browser). Very
> nice for self-serve access.  It does want to map complete hosts to
> owners that have permission to access them but with a little work you
> make different areas of a shared system look like separate hosts.
>
> --
>   Les Mikesell
>    lesmikesell at gmail.com
>
>
>
> _______________________________________________



BackupPC doesn't intergrate into cPanel.

-- 
Kind Regards
Rudi Ahlers
SoftDux

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