[CentOS-virt] proper way to snapshot

Thu Apr 26 18:21:26 UTC 2012
aurfalien <aurfalien at gmail.com>

On Apr 26, 2012, at 2:15 PM, Nux! wrote:

> On 26.04.2012 19:12, aurfalien wrote:
>> On Apr 26, 2012, at 1:54 PM, Nux! wrote:
>> 
>>> On 26.04.2012 18:23, aurfalien wrote:
>>>> Hi,
>>>> 
>>>> While there are a few howtos floating around, what is the standard
>>>> way to snapshot guests?
>>>> 
>>>> I went through and converted from raw to pre allocated meta data
>>>> qcow2 images for this purpose.
>>>> 
>>>> Some howtos suggest to do an xml snapshot file as so;
>>>> 
>>>> <domainsnapshot>
>>>>  <name>UbuntuServer_10.10-16032011</name>
>>>>  <description>Snapshot of OS install and updates</description>
>>>> </domainsnapshot>
>>>> 
>>>> And then to run as so;
>>>> 
>>>> virsh snapshot-create UbuntuServer_10.10 UbuntuServer_10.10-ss.xml
>>>> 
>>>> Seems a bit over kill.
>>>> 
>>>> I was thinking more along the lines of this;
>>>> 
>>>> qemu-img snapshot -c $date $filename
>>>> 
>>>> qemu-img convert -f qcow2 -O qcow2 -s $date $filename 
>>>> $filename-$date
>>>> 
>>>> Or something like this.Anyways, hoping to see how you all are doing
>>>> this for best practice sort of thing.
>>> 
>>> Hi,
>>> 
>>> I just use LVM snapshots; it's the fastest, most reliable way I 
>>> could
>>> come with.
>> 
>> Hi,
>> 
>> I don't have LVMs.
>> 
>> But if I did, would it be possible to only snapshot a directory or
>> will it snapshot the entire file system?
> 
> Assuming you use LVM on the host to provide the virtual machine with a 
> (virtual) HDD, then snapshotting that will obviously be (virtual) 
> disk-wise.

I used a simple non LVM partitioning scheme.

Can I do directory based snapshots in LVM or is it the entire FS?

I can re implement or redo my host to use LVM.

- aurf