Hi,
What is the best way for backing up urbackup datas on an usb disk ?
Rsync the /media/BACKUP/urbackup tu usb disk is enough ?
Thanks.
eric
Rsync would be the wrong way, because it would copy all the hard linked files, resulting in much more data.
The best/fastest way would be some kind of block level copying. If you use ZFS or btrfs you could use send/receive and snapshots. With LVM snapshots and dd. Otherwise unmount and dd. You could also build a software RAID 1 and sync the USB disk from time to time. If you really want to copy the files I heard something about cpio and afio preserving hard links. See http://jeremy.zawodny.com/blog/archives/010037.html . So you should use that. It would probably be much slower than block level copying, though.
EDIT: On the page somebody commented that rsync preserves hard links with the -H option. So you probably could use that as well.