On Thu, Nov 12, 2009 at 6:37 PM, Fajar A. Nugraha fajar@fajar.net wrote:
On Thu, Nov 12, 2009 at 5:10 PM, Mr. Teo En Ming (Zhang Enming) space.time.universe@gmail.com wrote:
Hi,
I don't think I will be using the LVM snapshot method. I will simply
ensure
that my domU is not running,
Ah, so you can live with the down time. It makes things a lot simpler then.
then I proceed to do the losetup and kpartx procedure.
Like others mentioned, you don't need losetup for LVs. It will only make things slower.
Subsequently I will backup the MBR of my domU by dd-ing /dev/loopX and clone all the filesystems of the domU using fsarchiver.
I would like to use fsarchiver because it can support LZMA compression.
LZMA
can compress better than bzip2 and decompress 3x faster than bzip2. partimage only supports gzip and bzip2.
If your concern is the size and speed of backup, here's one final note from me: you might want to look at zfs. Possible use scenarios :
- use opensolaris as dom0. Probably the most supported option when it
comes to xen + zfs, but you need to be familiar with how opensolaris works.
- use external storage server running solaris/opensolaris as iscsi
SAN. Think of it as poor-man's Netapp.
- use zfs-fuse inside Linux dom0, and store domU storage as files
- use zfs-fuse on domU, and do backup from domU instead of dom0.
With zfs, you'd get zfs snapshot (which is like instaneous in-place backup), incremental block-level send (can greatly reduce backup storage size if your data doesn't change often), optional transparent compression for live data (like what ntfs has).
-- Fajar
I am not familiar with OpenSolaris but that may change with time.