[Techtalk] rsync backup script

[Dan Shearer]

On Mon, Jun 21, 2004 at 04:41:01PM -0700, Carla Schroder wrote:
> Does anyone have a really really cool rsync script they'd like to share? 

This message is not directly answering the question.

I'll take a flying punt that you are wanting to use rsync for backup
purposes. If so, then here's an alternative suggestion that works very
well for backups for some networks I run. Personally I dislike the
interventionist nature of even the best-planned backups and so I'll go a
long way to make them transparent :-) 

I use and recommend RAID over network block devices. RAID0 is mirroring
(two discs get written to identically and simultaneously) and RAID5 is a
clever means of splattering data across more than two discs so that you
get redundancy and speed. 

Network block devices are described at http://www.it.uc3m.es/~ptb/nbd/ .
Imagine a disc in your machine, then imagine that the ribbon cable
suddenly got converted into a network cable accessible to some other
machine on the network. That's a network block device.

You can mirror two network block devices. This gives you an automatic,
real-time backup. If disc dies the other just keeps going. Recent
enhancement to the nbd driver make recovering from a mirror problem very
painless (just as well, because how often might you temporarily lose
connectivity to your disc the other end of a network wire? Every time
somebody reads the sign "DON'T UNPLUG THIS WIRE" and get's curious :)

You can even run RAID0 over two remote discs like this, only they aren't
remote discs they are remote RAID5 volumes across 4 or 5 discs each.

-- 
Dan Shearer
dan at shearer.org