A simple and crude Backup script for KVM qcow2 images from a remote logical volume.

backup.sh

#/bin/bash

VG="/dev/vg0"
SNAPSHOTLV="imagesnap"
SOURCELV="vm-images"
MOUNTPOINT="/mnt/snapshot"
DESTINATION="/mnt/Backup"

ssh root@server /bin/bash <<EOF
 lvcreate -l100%FREE -s -n $SNAPSHOTLV $VG/$SOURCELV
 mkdir -p $MOUNTPOINT
 mount $VG/$SNAPSHOTLV $MOUNTPOINT
EOF

IMAGES=$(ssh root@server ls $MOUNTPOINT/*.qcow2)
for img in $IMAGES; do
    if [ -e $DESTINATION/$img ]; then
        rsync -avh --progress --inplace  root@server:$MOUNTPOINT/$img $DESTINATION
    else
        rsync -Pavh --sparse  root@server:$MOUNTPOINT/$img $DESTINATION
    fi
done

ssh root@server /bin/bash <<EOF
 umount $MOUNTPOINT
 lvremove $VG/$SNAPSHOTLV -f
 rmdir $MOUNTPOINT
EOF

This assumes a host entry server in .ssh/config and a readily set-up ssh public key authentication as root on the remote site.
Remote files will be compared with local destination and updated in place, if they already exist. Otherwise a whole backup will me made in sparse mode, efficiently handling zero blocks.
Takes care of LVM snapshots and cleanup.