I would say 'no'. Let's say you have a DB app running in your host OS and it's in the middle of writing a transaction to a data disk...quiescing the VM - without quiescing the DB app (like SQL Server via VSS) - does not give you a properly quiesced snapshot on the data disk - just a point-in-time snapshot.
On Mon, Sep 30, 2013 at 3:52 PM, Chiradeep Vittal < chiradeep.vit...@citrix.com> wrote: > Is VM Quiescing sufficient to ensure consistency of the snapshot? > > > On 9/30/13 2:43 PM, "SuichII, Christopher" <chris.su...@netapp.com> wrote: > > >CloudStack currently snapshots vm disks by taking hypervisor snapshots. > >However, when implementing the storage subsystem API interface > >takeSnapshot(), the VM associated with the requested volume is not > >quiesced since a hypervisor snapshot is not necessarily taken. When > >creating a storage level snapshot, there are ways around this and > >'quiescing' the vm without actually quiescing it (through hypervisor > >APIs). I would like to propose that there be an option to quiesce VMs > >when taking snapshots both manually and through recurring snapshot > >policies. One issue I see with this is that this option is not always > >applicable. If the default storage provider is used, a hypervisor > >snapshot will be taken and therefore the VM will always be quiesced. Some > >storage providers may not respect the user's request to quiesce. Because > >of this, I suggest that the option be shown to the user as 'Quiesce VM > >(if applicable)'. This indicates to the user that the option will be > >passed to the management server and respected if possible. > > > >I will work on formalizing a full functional spec if needed but wanted to > >get this up for discussion ASAP. > > > >I have created a JIRA ticket: > >https://issues.apache.org/jira/browse/CLOUDSTACK-4774 > > > >Thanks, > >Chris > >-- > >Chris Suich > >chris.su...@netapp.com<mailto:chris.su...@netapp.com> > >NetApp Software Engineer > >Data Center Platforms Cloud Solutions > >Citrix, Cisco & Red Hat > > > > -- *Mike Tutkowski* *Senior CloudStack Developer, SolidFire Inc.* e: mike.tutkow...@solidfire.com o: 303.746.7302 Advancing the way the world uses the cloud<http://solidfire.com/solution/overview/?video=play> *™*
