Tim Post
2008-09-23 11:06:25 UTC
I managed to get both Xen-0 ops and ext3cow into the last 2.6.25
release, based on the OpenSUSE xen patches.
I created a logical volume (ext3cow) that was 20 GB in size. on it, I
created several file backed block devices (loops) for guests to use.
I paved the guests as ext3, populated them with deboostrap and booted
them using aio to connect the block devices. As each was booted, I took
a snapshot of its .img file
I could then mount the .img just as it was when I booted
(mount /guests/***@epoch), backup the virtual machine and the VM
was completely unaware of it. dd if=./***@epoch should also work to make
a snapshot to a LV without pausing.
This is not advisable in production (especially on long running
systems) .. but still cool.
Note, I issued sysrq S prior to doing this and have not tried it with
guests under stress.
Just fun to try if you happen to be bored. I'll soon publish a hg of the
xen patched kernel which will take the 2.6.25 ext3cow patch.
Cheers,
--Tim
release, based on the OpenSUSE xen patches.
I created a logical volume (ext3cow) that was 20 GB in size. on it, I
created several file backed block devices (loops) for guests to use.
I paved the guests as ext3, populated them with deboostrap and booted
them using aio to connect the block devices. As each was booted, I took
a snapshot of its .img file
I could then mount the .img just as it was when I booted
(mount /guests/***@epoch), backup the virtual machine and the VM
was completely unaware of it. dd if=./***@epoch should also work to make
a snapshot to a LV without pausing.
This is not advisable in production (especially on long running
systems) .. but still cool.
Note, I issued sysrq S prior to doing this and have not tried it with
guests under stress.
Just fun to try if you happen to be bored. I'll soon publish a hg of the
xen patched kernel which will take the 2.6.25 ext3cow patch.
Cheers,
--Tim