Disc based backups, snapshots, syncing (was Re: [tech] the aftermath)

[Nick Bannon]

On Sat, Nov 15, 2003 at 03:02:11AM +1100, David Luyer wrote:
> Has anyone done copy-on-write snapshots for Linux or *BSD?
> (most SANs do them, but I can't think of a Unix FS which does)

There's a few options - Linux LVM of course, at the block layer.

At the FS layer, there's BSD Union FS and
http://translucency.sourceforge.net/ , or a few other/older approaches
at the same thing.

User-Mode-Linux can, which would be quite a neat solution.

Then there's a bunch of disc-based backup systems. These would indeed
match a removable Firewire disc or something - I _do_ think they'd be
worth getting a nice big one (a dual drive LaCie?) and using
exclusively for backups:

http://www.mikerubel.org/computers/rsync_snapshots/
http://www.mikerubel.org/computers/rsync_snapshots/#References (Links)

http://rsnapshot.scubaninja.com/

And a few syncing-type links for luck:

How to do a consistent mirror, using sequence files:
http://www.ussg.iu.edu/hypermail/linux/kernel/0311.1/0442.html

http://0pointer.de/lennart/projects/syrep/

apt-cache show unison

RAID over NBD/ENBD/iSCSI/HyperSCSI?

http://www.drbd.org/

http://www.cs.bgu.ac.il/~srfs/overview.html

http://www.lustre.org/

It would of course be wonderful to pick up a secondhand NetApp filer,
in a complete and operational state. They keep getting put on ebay for
stupidly high prices, and... not selling.

Nick.

-- 
   Nick Bannon   | "I made this letter longer than usual because
nick-sig at rcpt.to | I lack the time to make it shorter." - Pascal