You might think, given that I wrote an article awhile ago about the Procedural Obligations of Backup Administrators that it wouldn’t be necessary to explicitly spell out any recovery rules – but this isn’t quite the case. It’s handy to have a “must follow” list of rules for recovery as well.
In their simplest form, these rules are:
Let’s look at each one in more detail:
- How – Know how to do a recovery, before you need to do it. The worst forms of data loss typically occur when a backup routine is put in place that is untried on the assumption that it will work. If a new type of backup is added to an environment, it must be tested before it is relied on. In testing, it must be documented by those doing the recovery. In being documented, it must be referenced by operational procedures*.
- Why – Know why you are doing a recovery. This directly affects the required resources. Are you recovering a production system, or a test system? Is it for the purposes of legal discovery, or because a database collapsed?
- Where – Know where you are recovering from and to. If you don’t know this, don’t do the recovery. You do not make assumptions about data locality in recovery situations. Trust me, I know from personal experience.
- When – Know when the recovery needs to be completed by. This isn’t always answered by the why factor – you actually need to know both in order to fully schedule and prioritise recoveries.
- Who – Know who requested the recovery is authorised to do so. (In order to know this, there should be operational recovery procedures – forms and company policies – that indicate authorisation.)
If you know the how, why, where, when and who, you’re following the golden rules of recovery.
* Or to put it another way – documentation is useless if you don’t know it exists, or you can’t find it!