Backup VMs stored on lvm

Someone has a backup system for backup VMs stored on lvm datastore (attached via iscsi to kvm nodes) for OpenNebula?

Hello, there is this backup script, Contribution: OpenNebula backup script for QCOW2 datastores, but actually without LVM support, but can be extended to support LVM.

It uses external snapshots with block commit, so can be used also for VMs using block devices.

after creating snapshot you can just dd if=/path/to/lvm/image of=/path/to/backup/file

after it you blockcommit external snapshot back to the original vm image.