Re: [Qemu-devel] Re: [et-mgmt-tools] Image Corruption Possible with qemu and qemu-kvm

[Sven Oehme]

address@hidden wrote
on 08/28/2007 04:13:02 AM:

> Anthony Liguori wrote:
> >> In the scenario you mention, libvirt should probably do a
sanity check for
> >> this before letting you start the guest. libvirt already
supports the idea
> >> of 'shared' disk images where two or more guests can be 
> optionally configured 
> >> to have write access - basically assumes the admin requesting
sharing knows
> >> what they're doing.
> >>     
> >
> > I think this is the right level myself.  Advisory locks
work okay but
> > not all filesystems support them.  It's particularly nasty
when you have
> > a clustered filesystem in the host.  I think it would do
more harm than
> > good to have a feature like that was supposed to provide a safe-guard
> > but then frequently didn't work.
> >   
> 
> There's still the unmanaged use case to worry about.  I think
qemu can 
> default to advisory locking, and management tools can do their own
> locking and always override qemu.
> 
> It's too easy to kill an image by starting up another instance right
now.
> 

i agree default should be advisory locking and a switch
to disable it ..
would that be hard to implement ?

thanks. Sven