Re: [Qemu-devel] PATCH: Control over drive open modes for backing file

[Anthony Liguori <anthony@codemonkey.ws>]

Jamie Lokier wrote:
> Anthony Liguori wrote:
>   
>>> Can I arbitrarily branch off different snapshots within a single qcow2
>>> file?  Can I delete the 'base' snapshots safely?  Most important: what
>>> happens if I have snapshots in a qcow2 file which has a base file, and
>>> I type 'commit'?  Does it corrupt all the snapshots, effectively?
>>>       
>> snapshots are linear, not branching.  And they are only every 
>> saved/loaded from the highest level qcow2 file.
>>     
>
> So if I understand that right, the 'commit' command (to write to the
> base image) _will_ corrupt all the snapshots since they depend on the
> base image and it just changed??
>   

Yes, so don't do that.

BTW, commit is a pretty useless command IMHO.  If you use it to save a 
snapshot of a disk image while the OS has it mounted, you're not getting 
a very good backup.

Regards,

Anthony Liguori

Regards,

Anthony Liguori

> -- Jamie
>
>
>