Fast snapshot backups for KVM

[twocell]

Aug 21 23:33:01 INFO: Starting Backup of VM 101 (qemu)
Aug 21 23:33:01 INFO: running
Aug 21 23:33:01 INFO: status = running
Aug 21 23:33:05 INFO: mode failure - unable to dump into snapshot (use option --dumpdir)
Aug 21 23:33:05 INFO: trying 'suspend' mode instead
Aug 21 23:33:05 INFO: backup mode: suspend
Aug 21 23:33:05 INFO: bandwidth limit: 10240 KB/s
Aug 21 23:33:05 INFO: suspend vm
Aug 21 23:33:05 INFO: creating archive '/var/lib/vz/dump/vzdump-qemu-101-2010_08_21-23_33_01.tgz'
Aug 21 23:33:05 INFO: adding '/var/lib/vz/dump/vzdump-qemu-101-2010_08_21-23_33_01.tmp/qemu-server.conf' to archive ('qemu-server.conf')
Aug 21 23:33:05 INFO: adding '/var/lib/vz/images/101/www-sewn.raw' to archive ('vm-disk-virtio0.raw')
Aug 22 00:45:55 INFO: Total bytes written: 64631567360 (14.10 MiB/s)
Aug 22 00:45:55 INFO: archive file size: 31.36GB
Aug 22 00:45:55 INFO: resume vm
Aug 22 00:45:55 INFO: vm is online again after 4370 seconds
Aug 22 00:45:56 INFO: Finished Backup of VM 101 (01:12:55)

I'm just testing now ... What do I need to do to get fast snapshot capability?

 

[l.mierzwa]

You need LVM for storage.

 

[dietmar]

Please choose a reasonable backup location using "--dumpdir"

Note: you can't store the result of a snapshot into the snapshot. That is an endless recursion.

 

[twocell]

I don't think I'm encountering a recursive situation here, just the .tmp files are stored in the same directory where the snapshot and log files end up.

Where should I put a local snapshot on my test system with just 1 hard drive? Does this also mean I need to use iSCSI for fast snapshoting to a remote filesystem?

I was thinking about having two servers in the cluster, storing the backups for one server on the other and vice versa. Is this reasonably easy to accomplish? My other thought was two proxmox servers and an openfiler storage server, but then the openfiler becomes a single point of failure.

 

[dietmar]

I don't think I'm encountering a recursive situation here, just the .tmp files are stored in the same directory where the snapshot and log files end up.

Both /var/lib/vz/dump and /var/lib/vz/images reside on the same LV - so this is indeed a recursive situation.

Where should I put a local snapshot on my test system with just 1 hard drive? Does this also mean I need to use iSCSI for fast snapshoting to a remote filesystem?

If your root filesystem is big enough, you can put it there. But that is a bit dangerous, because you can run out of space on root. So a second disk, or a remote filesystem would be the better solution.

I was thinking about having two servers in the cluster, storing the backups for one server on the other and vice versa. Is this reasonably easy to accomplish? My other thought was two proxmox servers and an openfiler storage server, but then the openfiler becomes a single point of failure.[/QUOTE]