Compression setting

[SQLBill]

I have been seeing a lot of questions concerning compression. I would like to make the following suggestion.

If you set up Veritas Backup Exec to use the tape drive/library drivers, set compression to HARDWARE COMPRESSION.

If you set up Veritas Backup Exec to use Veritas' drivers, set compression to SOFTWARE COMPRESSION.

I think this will solve most of the compression issues. It appears that the compression setting needs to match the drivers (software (BE) or hardware (tape drive)) being used.

-SQLBill

 

[GreenTeeth]

Can I just add a bit here too. I managed to get through to Veritas on this subject and they said that when you set compression to Hardware, all it does is send a signal out that hardware compression is on, but bear in mind, hardware compression is a hardware thing, and will only work if your hardware has it. We use HP and they have fairly comprehensive diagnostic tools that you can download from their site (URL is round here somewhere) and this can tell you if the compression is working. If it is, then you can rule it out as an option.

Not all data is compressable (microsoft Exchange is a good example of this the information store is already compressed) and so those rotten little figures on the tapes can be misleading, 12/24 GB means it can backup 12GB happily, and if you got anymore on, well done.