Just a quick note that openrsync is in the pkgsrc collection; might be worth testing. The openrsync executable can act as either client or server so for local-to-local archiving you can do something like
$ openrsync --rsync-path openrsync -av --delete ../source ../dest where openrsync basically calls itself for the destination end. I haven't tested this yet with an ext2 mounted filesystem and would be very interested in hearing about any testing done with it. -b
