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DW027A and BackupExec 11d hardware compression

Marcus Freeman
Occasional Advisor

DW027A and BackupExec 11d hardware compression

In Backup Exec 11d My compression ratio is 1.04:1 eventhough hardware compression is set to enabled. In Storageworks tape tools, I have enabled compression with the configuration utility.
5 REPLIES
Marcus Freeman
Occasional Advisor

Re: DW027A and BackupExec 11d hardware compression

A tape takes 4.3 hours to write.
Marcus Freeman
Occasional Advisor

Re: DW027A and BackupExec 11d hardware compression

Using the Storageworks tape tools, the 64MB compression test yields 2.23:1 compression.
Marcus Freeman
Occasional Advisor

Re: DW027A and BackupExec 11d hardware compression

Updated to latest device driver version 1.6.0.0 dated 11/01/2007.

Now I am seeing the following in the L&TT compression test:

! Before running this test, L&TT determined that your hardware compression algorithm is switched off.
! This was probably set by your backup software.
! L&TT has not altered your setup.

Backup Exec 11d diagnosic shows that [Compression Hardware] = 0x1

Any combination of confiurations with L&TT or Backup Exec (w/service restarts) has been tried. still getting 1:1 throughput.

Help!


Rob Leadbeater
Honored Contributor

Re: DW027A and BackupExec 11d hardware compression

Hi Marcus,

The level of compression that you'll get will depend entirely on the type of files that you're backing up, and whether they're already compressed.

For example, if you try to back up GIF images, or ZIP files, these are already compressed formats, so the tape drive won't be able to compress them further.

Hope this helps,

Regards,

Rob

P.S. You might want to close your other duplicate thread...
Marcus Freeman
Occasional Advisor

Re: DW027A and BackupExec 11d hardware compression

No, there is something wrong with the driver.

A full backup to 1 DAT72 tape is 32GB and takes 4+ hours per tape. Compression is not enabled as the driver in device manager is displayed.

I've tried 3 re-installs of backup exec as it gives the option to use propietatry, windows, or the existing hp oem drivers. I am using 1.6.0.0 for the Tape Drives driver. In all cases, device managers driver info seems to be replaced when the backupexec service starts. the multitabbed driver information disapears and when the service is stopped reappears, at which time the tab for configuration shows: COMPRESSION=FALSE. However backupexec's diag always shows 0x1 for compression.