Re: [Qemu-devel] [PATCH 0/2] virtagent - fsfreeze support

[Richard W.M. Jones]

On Tue, Feb 01, 2011 at 02:25:12PM +0300, Vasiliy G Tolstov wrote:
> On Tue, 2011-02-01 at 11:58 +0100, address@hidden wrote:
> > From: Jes Sorensen <address@hidden>
> > 
> > Hi
> > 
> > This is a first attempt to add fsfreeze support to virtagent. The idea
> > is for the guest agent to walk the list of locally mounted file
> > systems in the guest, and issuing an ioctl to freeze them. The host
> > can then do a live snapshot of the guest, obtaining stable file
> > systems. After the snapshot, the host then calls the thaw function in
> > virtagent, which goes through the list of previously frozen file
> > systems and unfreezes them.
> > 
> > The list walking ignores remote file systems such as NFS and CIFS as
> > well as all pseudo file systems.
> > 
> > The guest agent code is in the first patch, and host agent code is in
> > the second patch. For now there is only human monitor support, but it
> > should be pretty straight forward to add QMP support as well.
> > 
> > Patches are against the virtagent-dev git tree.
> > 
> > Comments and suggestions welcome!
> > 
> > Cheers,
> > Jes
> 
> Hello. Very nice feature. Sorry for offropic, but can this feature can
> be used to modify partiotion table on already mounted device (for
> example root on ext3? )

There are some experimental patches to libguestfs to do live
filesystem and partition manipulations now:

  https://www.redhat.com/archives/libguestfs/2011-January/msg00096.html

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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