vzdump

vzdump is a utility to make consistent snapshots of running OpenVZ VEs. It basically creates a tar archive of the VE private area, which also includes the VE configuration files.

There are several ways to provide consistency:

stop the VE during backup (very long downtime)
use rsync and suspend/resume (minimal downtime)
use LVM2 (no downtime)

vzdump is available here:

source code:	vzdump-1.0.tar.gz
RPM:	vzdump-1.0-2.noarch.rpm
DEB:	vzdump_1.0-2_all.deb