Wednesday, 24 March 2010

NOTE: Clean-Up, But Don't Lose Anything (omabakup)

My talk of spring-cleaning reminds of days spent searching for stuff in my home-office only to find that my dear wife had spring-cleaned them to somewhere "more suitable" but less obvious to me. In these cases I hadn't actually lost them, but for a period of time I believed I had.

Losing some of your SAS data or metadata could be far more costly to your business than me losing my favourite pen from my desk, so you'd better to be doing good, reliable, regular and frequent backups. In most cases, sites are pretty good at backing-up disks using standard back-up routines, but the SAS metadata server's data needs special attention. Read on...

Before backing-up your metadata repositories, you need to pause the metadata server so that there are no attempts to change the data whilst it's being backed-up. Without pausing the metadata server you may find that the back-up fails or (worse) you may find that your back-ups are useless and cannot be restored.

The easiest and most effective means of pausing, backing-up, and then unpausing is to use SAS's supplied omabakup facilities. The SAS install/config process creates backupServer.sas and restoreServer.sas in your SASMeta\MetadataServer directory(s). These are pre-configured to suit your environment. backupServer.sas writes the backup files to a subdirectory called SASBackup in the MetadataServer directory. After backupServer.sas has run, your standard back-up routine can backup the contents of this directory at its leisure.

Alternatively, you can use the Backup Wizard from the Metadata Manager node in Management Console. This allows you to create jobs for immediate execution, or for later; and it automatically creates an equivalent restore job too. Tidy!

SAS offers advice about best practices for back-ups and restores in the SAS 9.2 Intelligence Platform: System Administration Guide. And, not surprisingly, Angela Hall's SAS-BI blog offers more than one valuable insight and tip for the use of omabakup.

Back-ups of your business data are crucial to the safe operation of your business, but they must be effective. Back-ups of your SAS metadata will not effective unless you are aware of the need to pause the metadata server beforehand. Using one of the facilities provided by SAS, you can be assured of reliable back-ups of your valuable metadata.