Compression from 2 Backup Servers on 1 Fibre Library [2 LTO-4 Tape Drives]

[MGBackup]

Alright, here's the set up - I have one MSL4048 Tape Library with 2 LTO-4 Tape Drives installed. There are 2 backup servers that have access to it via fibre and a fibre switch. I have their slots partitioned in Backup Exec so that each server only uses it's assigned slots, but can use whichever drive is available. Both jobs were set to use Hardware Compression if available; otherwise, none. One server's full backup job kicked off and worked great, using the hardware compression. The other server's job started a little later, but didn't compress like I was expecting. It showed a 1:1 compression ratio and was going through way too many tapes (7 TB to back up). Why wasn't it compressing? Is compression only available for one job in a library and not for each drive?

Much oblidged!

[Ken_Putnam]

Compression on each should not be a problem (hardware compression, right?)

Have you tried submitting a  job with compression to the second drive while the first is idle?
Have you tried a compression job from the media server that worked to the questionable drive?
Have you tried a few passes of the mfg diagnostics against the second drive?

[Hemant_Jain · Accepted solution]

Please confirm, if "Enable compression is checked in the tape drive properties of both the drives. Also, try running sgmon and identify if backup Exec turns on compression in both cases. Also compare the drivers for tape drive on both the servers. Do you have same drivers on both the servers?

[MGBackup]

Please confirm, if "Enable compression is checked in the tape drive properties of both the drives.

Well, it looks like this was probably the culprit and I made it more difficult than I needed to! When the current jobs finish, I'll try another job with those boxes checked and let you know it worked.

Thank you!

[MGBackup]

It worked!

Thanks again!