[LUNI] on-disk backups

[Fred Yankowski]

Anyone interested in on-disk backup (as opposed to backup-to-tape)
might want to read "Easy Automated Snapshot-Style Backups with Linux
and Rsync":  http://www.mikerubel.org/computers/rsync_snapshots/

I've been trying the scheme described there on a web server, and it
works great.  Basically, the approach takes a snapshot of all files
(to be backed up) every N hours, rotating older snapshots every time
and keeping some given number of snapshots around.  The clever part is
how the approach uses rsync and hard links so that any given version
of a file's contents is backed up only once:  when an unchanged file
appears in multiple snapshots, the instances of that file (same
relative name) are all hard links to the same content/inode.  The net
is that each snapshot is a complete view of the backed-up set of
files, without the overhead of keeping multiple copies of unchanged
files on disk.

-- 
Fred Yankowski      fred at ontosys.com           tel: +1.630.879.1312
OntoSys, Inc	    PGP keyID: 7B449345        fax: +1.630.879.1370
www.ontosys.com     38W242 Deerpath Rd, Batavia, IL 60510-9461, USA