[Scottish] Backing up

Colin McKinnon scottish at mailman.lug.org.uk
Tue Oct 22 15:33:01 2002

David Irvine wrote:

>Most of us keep some form of backups but its not exactly rock solid, The
>majority of the data is backed up once a month (data doesnt change much
>and its not critical data, just off site backups of customers set-ups.) 
>The problem is the smaller data which resides in users home directories
>or on laptops etc, which ironically is the critical data, not very large
>amounts, but it changes a lot, and is deemed very important both to
>company and to users. 
>What backup stratagies are people using? And what pitfalls/benefits do
>they have?
For the systems I look after, we do tape backups of either the full 
system or divided up between standard programs / operating system and 
data. I've never really liked the idea of rolling forward incremental 
backups manually. It's mostly database files that we're backing up so 
keeping the system coherent is very important. Another superstition I 
have is not using esotirc backup software. I don't doubt that there are 
great performance benefits, particularly when restoring selected small 
files, using Vertias (say) rather than tar, but my main concern with 
backups is how quickly I can get a system up and running after a major 
failure. I don't want to be running around tracking down software (and 
agents) in that situation.

When I get round to it, I'm going to put in gigabyte ethernet and dump 
the stuff to disk nightly but still take weekly offsite tapes. Most 
likely it'll be a box with Linux and as many IDE drives as I can fit in. 
(OK, so 100baseT is about the same speed as DDS4...but I'd rather just 
implement an improved solution from day1).

>I have set a script on most of the laptops that allows users to do a
>full backup of their system (using tar) if they like, but this isnt very
>economical on space or bandwidth.
Mirroring. There's lots of tools of synchronizing with remote systems. I 
wrote one of them - called PushSite - which includes a list of some of 
the other programs available. 
PushSite is quite stable/reliable now, although it doesn't send hidden 
files and doesn't like filenames with spaces in. Rsync is good for very 
large files which don't change much (e.g. database files).