Tuesday, November 21, 2006

Backups: Rotation of backups

What’s your approach? I’m asking... because for SMB clients, I’ve heard literally every possible combination of tactics, all with the same strategic aim - protecting the business.
Here’s what I do - not saying it’s perfect... certainly not saying it’s the only way... but it’s working for us internally, and is basically what we do/recommend for clients (depending on their risk profile, budget, and expectations).

  1. Nightly full backups of everything that’s "business critical", with a two-week rotation.
  2. At the beginning of each week, the last completed backup is taken off-site, and the previous one is returned.
  3. At the end of every month, the most recent completed tape is taken out of rotation and stored off-site.
  4. At the end of the year, a tape is taken off-site and stored permanently.
This gives us the ability to restore data from any day in the past two weeks, end-of-month for the past 12 months, and end-of-year for the past N years. The reason that I chose nightly full backups is because relying on the weekly tapes and daily incrementals introduces more risk. Now, there are some other components not covered here - archive shares, web servers, and so on... those are all covered by a separate monthly policy for non-business-critical assets.

What do you think? Obviously the more tapes we include the more options we have... but in general terms do you have any suggestions for improvement?

2 comments:

Anonymous said...

This is a great setup an exactly what I do with with my clients.

Client with lots of data I've got the dilemna of full backups daily. I have no answer yet, so we've been rotating two 750 gig drives every other week, each drive containing 5 days of backups.

Not a good system as we can't go back a month, a year but currently I have no other answers.

Thoughts, suggestions?

Nick said...

We considered using Microsoft's DPM internally. The pricing doesn't look too prohibitive ($950 for 3 servers as I recall).

Obviously, this isn't going to cover your off-site concerns, but it is really useful for doing quick point-in-time recovery for the last "X" number of days. You could combine it with a rotating hard drive approach, such that myabe you used DPM for 4-weeks of data, and then 2 or three hard drives for monthly backups which you take off-site.

Also, there's a number of internet-based backup services that I've looked into - including some where you just buy the software and configure everything yourself. So far, I havn't been really impressed with anything.


I still like properly-sized full nightly backups with end-of-week/month/year stored off-site.