Hello all, I''m sure it''s a frequent question asked a lot of time, But is it possible to backup domU without stopping it ? Else could you please give me some url talking about the subject ? (it''s difficult to find something in the list archives)
Mathieu Kretchner wrote:> Hello all, > > I''m sure it''s a frequent question asked a lot of time, But is it > possible to backup domU without stopping it ? > Else could you please give me some url talking about the subject ?If you''re using LVM then I believe you should be able to snapshot the domU LV and then backup via the snapshot without stopping the domU. Aaron
On Fri, May 16, 2008 at 02:55:13PM +0200, Mathieu Kretchner wrote:> I''m sure it''s a frequent question asked a lot of time, But is it possible > to backup domU without stopping it ?No. But some things like checkpointing are possible.. What exactly do you want to do? Rich. -- Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones virt-p2v converts physical machines to virtual machines. Boot with a live CD or over the network (PXE) and turn machines into Xen guests. http://et.redhat.com/~rjones/virt-p2v
On Mon, May 19, 2008 at 08:54:36AM +0200, Mathieu Kretchner wrote:> I would like a backup system tool like vmware offer. In other words how to > have a maximum availability with my domU fully backuped ?Just choose your favourite back up program and run it inside the guest. Treat the guest as you would any other machine. It''s not possible to do the backups entirely from the dom0. Rich. -- Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones virt-top is ''top'' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://et.redhat.com/~rjones/virt-top
Mathieu Kretchner wrote:> Are you speaking about LVM in the FS of the DomU or in the FS of Dom0 ?I meant using LVM on the Dom0 and then using an LV as the backing filesystem of the DomU. Aaron P.S. Please don''t top-post, it''s hard to follow.> Aaron Clark a écrit : >> Mathieu Kretchner wrote: >>> Hello all, >>> >>> I''m sure it''s a frequent question asked a lot of time, But is it >>> possible to backup domU without stopping it ? >>> Else could you please give me some url talking about the subject ? >> >> If you''re using LVM then I believe you should be able to snapshot the >> domU LV and then backup via the snapshot without stopping the domU. >> >> Aaron >> >> -- >> Fedora-xen mailing list >> Fedora-xen@redhat.com >> https://www.redhat.com/mailman/listinfo/fedora-xen >
Mathieu Kretchner wrote:> Do you have good how to about backup a LV ? and creating a domU in an LV ? >Google for "LVM2 snapshot" or look at the "snapshot" option on the man page for "lvcreate" to answer the first half of your question. Here is a snippet of the cron script that I run twice a day to backup all of my guests while they are running.> /usr/sbin/lvcreate --extents 100%FREE --snapshot --name vmsnapshots /dev/vms/vms > /bin/mount /dev/vms/vmsnapshots /vmsnapshots > DAY="`date +%A-%H%M`" > /usr/bin/time --format "%E" /bin/tar --sparse -zcvf /mnt/ssbackup01/vms-$DAY.tar.gz /var/lib/xend/domains /vmsnapshots > /bin/umount /vmsnapshots > /usr/sbin/lvremove --force /dev/vms/vmsnapshotsI am also interested in seeing a detailed howto for the "creating a domU in an LV" part of your question. I currently do live backups of all of my virtual machines using LVM2 snapshots but I had to put my virtual machine images in files instead of partitions to accomplish this. I never successfully created a virtual machine in an a logical volume partition. Some people say that I am sacrificing performance by putting my virtual machines in files. If that is true, then I''d love to see a detailed example of creating an arbitrary Xen guest image in a a logical volume. -- Good luck, Aaron Metzger
I have created PVMs in LVM partitions in the past. I assume that HVMs would be similar. I believe I was using CentOS 4 at the time, and I had to use the complete /dev path instead of the shortcut you get used to with most distros (including CentOS). Also, I was using standard XenSource rpm-installed manually-configured xen in runlevel 3, so I don''t know if you can do that through the Fedora tools or even with the Fedora Xen. However, you might give it a shot. Unfortunately, I am not currently messing with LVM, so I can''t give you any kind of detail on this (such as an example complete /dev path vs shortcut). Dustin