Re: [OT] Backup solutions - my preferences
On Thu, Mar 20, 2003 at 01:04:08PM -0800, Alvin Oga wrote:
> On 20 Mar 2003, Glenn English wrote:
> > 1) tape - can easily back up the entire system (and a small network)
> > 2) DDS - others are faster, but they cost more
> > 3) amanda, amanda, and amanda - command line, cron-able, free, and very
> > reliable
Agreed!
> i dont have time to play with tapes.. daily changing it..
> - forget one day... and you're hosed
Haven't used amanda, have you? Just set yourself up with a
decent-sized holding disk and it's not a problem. (Your backups will
finish fast, too.) My amanda server at work can easily run a week's
worth of backups without needing a tape, just saving it all up on the
holding disk. Just be sure the holding disk is a separate physical
device to minimize the chance of losing it if the system's primary
drive fails.
Or, of course, if you have the money to spare, you can buy a changer
and let the robot play with tapes for you.
> i prefer 100GB - 1TB of disks to be backed up to other disks ...
> ( tapes are too small for "full backups" and definitely too slow )
I presume that's a home system, right? I can't think of any sort of
professional setup where you would have that much data to back up and
not have the money for a tape changer.
By way of comparison, I work at a manufacturing plant. Home
directories for ~80 users, plus the company databases total out to a
little under 30G. Using amanda, I'm getting full dumps of everything
at least once a week, with nightly incrementals of anything that's
not doing a full. Totals out to about 7G a night going onto tape,
taking 13 minutes to collect all the data onto the holding disk and a
three and a half to four hours to write it to tape.
On the 20G tapes I currently use, I could handle pretty close to 100G
without any additional hardware or changes to my backup
configuration, although my 30G holding disk would only handle one or
two days' backups without a tape change, rather than a week. Dumps
to holding disk would still take well under an hour and writing the
tape would be under half a day. So what's "too small" and
"definitely too slow" there?
> - i want the backup to be live within a few minutes
> of the main server going down for whatever reason
Sounds like you want a redundant server more than a backup solution.
Even if no human intervention is required, you're going to need more
than "a few minutes" to copy 100GB-1TB from one hard drive to
another.
> - i assume "yesterdays or last weeks" tape/disk/backups is BAD
> and can still receover everything from day before or tonights
> backup ...
"BAD" in what way? Obsolete? That's why you do nightly
incrementals. Or do you expect the media to decay within 48 hours?
> - i want a "hands off backup"... if i go away for vacation
> for a week/month... the systems are still properly backed up
> ( semi-guaranteed )
That's exactly what you get from amanda with a suitably large holding
disk or (preferably) a changer.
> - i can lose 2 FULL backups and still recover everything
Cool. So can I - I run a one-week backup cycle and keep three weeks'
worth of tapes.
Now, I'm not saying that you shouldn't use disks if that's what makes
you happy. I don't care how (or even if) you back it up. But your
criticisms of tape are, by and large, incorrect and/or misleading.
I only mean to correct them.
--
The freedoms that we enjoy presently are the most important victories of the
White Hats over the past several millennia, and it is vitally important that
we don't give them up now, only because we are frightened.
- Eolake Stobblehouse (http://stobblehouse.com/text/battle.html)
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