On Wed, Sep 25, 2019, 10:20 AM mark <m.roth at 5-cent.us> wrote: > > Someone mentioned commercial software - I've cloned systems, esp. compute > nodes in a cluster - with rsync. Problem with rsync clones, they are asynchronous each file is copied separately so if the system is live and making changes, for instance a database server, the copy is not coherent. the ZFS file system is perfect for this stuff, you can snap shot and then ZFS send the snapshot or a delta between that snapshot and a previous snapshot and that creates a totally coherent copy made at a single point in time atomically.