[ClusterLabs] Antw: Re: snapshots in a clvm environment - some questions for proceeding

[Lentes, Bernd]

----- On Mar 1, 2017, at 8:11 AM, Ulrich Windl Ulrich.Windl at rz.uni-regensburg.de wrote:

>>>> Digimer <lists at alteeve.ca> schrieb am 24.02.2017 um 19:20 in Nachricht
> <8762afa9-0f45-04c7-2404-565dcabf9112 at alteeve.ca>:
> 
> [...]
>> Aside from this, I strongly recommend against snapshots as a backup
>> mechanism anyway. There is no way to ensure that that operating system
>> and applications are in a clean state when you take the snapshot, so
>> using the image is like recovering from sudden power loss. If data was
>> in cache but not flushed out, you could have corruption.
>> 
>> If you can't stop your VMs, I'd recommend using a backup application
>> inside the VM that knows how to ensure that your apps and the OS are in
>> a clean state, particularly for DBs.
> 
> Actually that's what we are doing, but at some point in the past I had ruined
> the directory with the VM images (user error). THe problem then was that you
> need a running VM to restore files inside the VM. This is when you would like
> to have a crash-consistent backup image of your VM. However I found no working
> solution yet (we have VM images hosted on OCFS2, hosted on a cLVM LV).
> 

I changed the approach. Inside the vm i have also lv's. When changing configuration inside the vm
i will snapshot inside. 


Bernd
 

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