Thanks for interesting discussion. I am looking for a solution that would allow migration (shared storage) and have ability to take snapshots. Hence CLVM looked like a place to look in to.
-nb --- On Tue, 12/29/09, Pasi Kärkkäinen <[email protected]> wrote: > From: Pasi Kärkkäinen <[email protected]> > Subject: Re: [rhelv5-list] CLVM and snapshots....supported ? > To: "Red Hat Enterprise Linux 5 (Tikanga) discussion mailing-list" > <[email protected]> > Date: Tuesday, December 29, 2009, 2:07 PM > On Tue, Dec 29, 2009 at 11:57:52PM > +0200, Pasi Kärkkäinen wrote: > > On Tue, Dec 29, 2009 at 10:50:52AM +0000, John Haxby > wrote: > > > 2009/12/28 Pasi Kärkkäinen > <[1][email protected]> > > > > > > On Mon, Dec 28, 2009 at > 03:51:59PM +0000, John Haxby wrote: > > > > 2009/12/28 > J Newbie <[1][2][email protected]> > > > > > > > > Btw, > any other recommendation for backing up virtual machines. > > > > > > > [snip client-hosted backup] > > > > > > > > > > We'd really need something > like Windows VSS, to be able to coordinate > > > the disk snapshots with the > apps running in the guest.. > > > > > > That is possible and you don't need > any especial software to do it. At > > > least I didn't, not quite anyway. > > > > > > > Yes, of course it can be done with custom scripts. > > > > I meant that it would be extremely good to have > something similar as VSS > > for Linux. Standard method to make safe/consistent > backups. No need for > > everyone to implement their own scripts :) > > > > > > > I had a shell script that put the > applications I was interested in into a > > > "safe" state -- depending on the > application this was either a suspend or > > > just shutting it down (sendmail, for > that one) -- did a sync and the > > > reported back to the host that the > guest was ready for a snapshot. When > > > the snapshot had been taken the > applications were either allowed to > > > continue or restarted as necessary. > > > > > > This isn't perfect: the guest file > systems are still marked dirty, but the > > > sync ensures (I hope) that all the > data is recoverable. > > > > > > Getting clean file systems would > require a change to the kernel so that > > > all disk activity is stopped and the > various file systems are briefly > > > marked clean while the snapshot is > taken. I don't know if anyone, > > > anywhere, is looking at that. > > > > > Linux 2.6.29 added generic filesystem freeze feature: > > http://lwn.net/Articles/287435/ > http://kernelnewbies.org/Linux_2_6_29 > > So all the needed things are there. Someone just should > make this simple > library/API that can coordinate the > snapshot/sync/flush/freeze process > with the guest and the apps in the guest. > > -- Pasi > > _______________________________________________ > rhelv5-list mailing list > [email protected] > https://www.redhat.com/mailman/listinfo/rhelv5-list > _______________________________________________ rhelv5-list mailing list [email protected] https://www.redhat.com/mailman/listinfo/rhelv5-list
