Back up tapes - how far back?

[sonofsanta]

Morning my lovelies.

One of my techies found an old email that had been printed out from last May - before I started, when the previous NM was migrating from CC3 to a vanilla 2k3 setup - where a parent has (justifiably) complained about his daughters coursework being lost. Now this was an unusual occurence because of the migration, and won't happen again, and I do sympathise with him. In said e-mail, though, he posited the idea of keeping weekly backups for 2 years in order to cover any eventuality where coursework might be lost.

2 years?!

Seems to me that that is a little bit of overkill. We currently have 4 weeks of backup - Monday to Thursday are overwritten weekly and Friday has a rotation of 4 sets of tapes, hence 4 weeks - and this to me seems entirely adequate and reasonable. Having 104 weeks x 6 servers = 624 tapes, and the room to store them safely (i.e. fireproof), seems entirely unreasonable.

Which got me wondering - how long do you keep your backups stored for? Am I asking for trouble with only 4 weeks? Just how far does our responsibility to mollycoddle the kids extend, and at what point do they have to take responsibility for checking and reporting losses to us within a reasonable timeframe?

And if any of you say you do 2 years to make me look bad I may well go and sulk. So there.

[jamesreedersmith]

If there was a migration i would expect to have a full set of pre migration backups kept for a good while (couple of years) but normal backups you sound spot on.

Thanks


james

[danrhodes]

We run the same as you but with the addition of a 6 monthly full backup tape and a year full backup tape both on rotation. We also backup to a NAS offsite weekly.

[AIT]

full backups daily monday to friday (on all storage) - overwritten each week
incremental backup of all other servers - overwritten each week

full backup weekly (all server) - overwritten every month week1 week2 etc
full monthly (all servers) - over written every year january, feb etc
full yearly (all servers) - kept for a minimum of 5 years.

[danrhodes]

full backups daily monday to friday (on all storage) - overwritten each week
incremental backup of all other servers - overwritten each week

full backup weekly (all server) - overwritten every month week1 week2 etc
full monthly (all servers) - over written every year january, feb etc
full yearly (all servers) - kept for a minimum of 5 years.

Good planning, do you have a disaster recovery plan, we have had to put our into action a few times when some of our sites have got burned to ashes, it's surprising how thankfull schools are when you can have their email server up and running the day after the school burns down, and their data available after 2 days!

D

[Abaddon]

Same here - minimum 5 years.. I can currently go back nearly 8 years. We are now disk-disk-tape, with tape being monthly, and the backup/mirrored disks being in a dedicated DR room with full snapshots of the core servers (we are all vitualised here).

[AIT]

Good planning, do you have a disaster recovery plan, we have had to put our into action a few times when some of our sites have got burned to ashes, it's surprising how thankfull schools are when you can have their email server up and running the day after the school burns down, and their data available after 2 days!

D

We do indeed have a disaster recovery plan.
Thankfully we have never had to use it. But I would say including ordering new hardware up within 2 days.
Or several hours if all servers haven't been burnt to a crisp.

[sonofsanta]

full backups daily monday to friday (on all storage) - overwritten each week
incremental backup of all other servers - overwritten each week

full backup weekly (all server) - overwritten every month week1 week2 etc
full monthly (all servers) - over written every year january, feb etc
full yearly (all servers) - kept for a minimum of 5 years.

That sounds like an appropriate mix of overkill and economy that is much more suitable. Possibly 7 years to cover the entire career of a student in school would work.

Works out at 4 daily + 4 week + 11 month + 5 year = 24 x 6 servers = 144, where the 30 yearly tapes could be kept off-site and probably the 66 monthly tapes as well - not going to need urgent access to them on a regular basis, I would imagine.

How often have you had to go back to those older backups though? Do people honestly remember a file they last had 4 years ago and ask for it back?

[maniac]

Monday - Thursday tapes are over written every week
4 Friday tapes on Rotation, over written every month
12 end of Month tapes, over written every year.

I've never seen any justification for keeping a backup any longer than this.

Works for us, although I've never had to recover work from them as we run shadow copies which goes back 60 days at the click of a mouse - most students should hopefully realise their work is missing within this time!

Mike.

[AIT]

That sounds like an appropriate mix of overkill and economy that is much more suitable. Possibly 7 years to cover the entire career of a student in school would work.

Works out at 4 daily + 4 week + 11 month + 5 year = 24 x 6 servers = 144, where the 30 yearly tapes could be kept off-site and probably the 66 monthly tapes as well - not going to need urgent access to them on a regular basis, I would imagine.

How often have you had to go back to those older backups though? Do people honestly remember a file they last had 4 years ago and ask for it back?

and oh yes staff definitely remember files they had 5 years ago... including powering up an old vm of cmis.

p.s. we are a little over kill on the old backups but better to be safe than sorry.

[Abaddon]

I was told that SIMS (and therefore, any MIS) data had a regulatory 3 year retention period...

[sonofsanta]

I was told that SIMS (and therefore, any MIS) data had a regulatory 3 year retention period...

Wouldn't that be covered by simply having the old datasets available for that length of time? I know that our intention (going forward) is to have 7 years of datasets available, and as that database is backed up by our normal policy we would always have that to hand.

[Abaddon]

During a recent inspection, they actually wanted to SEE the tapes, and the backup policy.

[pete]

We backup to disk...

Incrementals Mon-Thurs
Full on Friday, kept for minimum of 4 weeks. Encrypted and dumped to tape for offsite storage.
We also keep the first backup from the beginning and the end of every term for a year because it's a cheap fix for random daftness.
Student work (after they've left) gets deduped, compressed and dumped to DVD and kept for a couple of years.