lvs
lvcreate -L 1GB -s -n mysnap /dev/xen-vol/my-disk
mkdir /mnt/snap
mount /dev/xen-vol/mysnap /mnt/snap
tar -zc /mnt/snap/ | ssh -i foo.rsa chris@remoteserver "cat > /media/big/snap.tgz"
umount /mnt/snap
lvremove /dev/xen-vol/mysnap