Re: [linux-lvm] snapshots and nfs

["Randall A. Jones" <rajones@svs.gsfc.nasa.gov>]

Kristina Clair wrote:

>On Tue, 18 Jan 2005 19:44:49 +0000, Alasdair G Kergon <agk@redhat.com> wrote:
>  
>
>>On Tue, Jan 18, 2005 at 12:36:06PM -0500, Kristina Clair wrote:
>>    
>>
>>>so, is there a way to have lvcreate not suspend the volume?  I'm using
>>>xfs, so I should be able to freeze the filesystem.
>>>      
>>>
>> 
>>Quick question: you're not running xfs_freeze are you?
>>If so, try without, as device-mapper does the equivalent of that
>>internally and xfs can't handle things if it gets run twice.
>>    
>>
>
>No, if I run xfs_freeze first, lvcreate hangs when it tries to suspend
>the volume, so I stopped doing that.
>Now, if I run lvcreate shortly after the machine is booted, it runs
>successfully.  However, if I try to run the same command the next day,
>after it's been online and the webservers have had the filesystem
>mounted, it hangs when trying to suspend the volume.
>
>  
>
Is it possible that mounting the NFS mounts on the webservers read-only 
as a temporary measure while creating the snapshot will help?

>So I'm wondering if the problem is that the webservers have the
>filesystem mounted and in use (apache is serving pages from it),  I'm
>trying to find a way to keep the filesystem mounted over nfs but still
>be able to create snapshots, and I was wondering if I could use
>xfs_freeze and have lvcreate not try to suspend the volume.
>
>Thanks,
>Kristina
>
>  
>
-- 
..:.::::
Randall Jones     GST      NASA Goddard Space Flight Center
HPC Visualization Support       http://hpcvis.gsfc.nasa.gov
Scientific Visualization Studio    http://svs.gsfc.nasa.gov
rajones@svs.gsfc.nasa.gov      Code 610.3      301-286-2239