Vitaliy wrote:

> Yeah, we do that for source code and stuff. I got into the habit of
> committing in small chunks, it makes documenting the changes so much
> easier.

Yes, and going back to the version that did work before I did my latest
extremely smart changes :)

> So, how many drives do you keep around? And what exactly is your backup
> procedure? Do you back up only the incremental changes to a single 500GB
> drive?

At the end of a week, I start a new backup cycle with a new base line
(full) backup. Each day during the week I add an incremental backup to
that. I keep two full weeks of these daily backups, plus a selection of
baseline backups that go back at least two months. Every week I take a copy
of all this to an offsite location. One drive is internal and is where I do
my backups to. Another drive has a copy of that (to be taken offsite at the
end of the week), and still another drive is offsite during the week
(coming onsite at the end of the week).

(Ok, that offsite thing is on hold until I get to the US the next time and
buy a couple of USB 2 external drives, but the idea is as good as done :)


> It seems to me that a hybrid system (drives for short-term stuff, tapes
> for long term) is the best solution, from POV of
> cost/reliability/simplicity.

Maybe, maybe not. 

I don't like tapes for simplicity. I used to think that they were a good
idea, but my experiences were that they never worked well. YMMV, of course,
and I didn't have the real high-end stuff. (But if you have, cost becomes a
major factor.) I think there are few other media that are as simple to use
as hard disks.

I'm not sure tapes are as reliable as hard disks for long term storage. I'm
pretty sure that a hard disk can be read in ten years; I wouldn't be so
sure with tapes. (I'm not talking about interface and protocol issues, just
about media.) The only damaging factor where they have an advantage is
shock, but that can usually be prevented, and generally will be noticed
right away if it happens and can be taken care of. 

And cost... are you sure that your cost per GB is lower with tapes than it
would be with hard disks?

Gerhard

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