We typically install HP Tape Drives & Symantec Backupexec.
In 2010 we installed a HP USB DAT 160 with Symantec Backupexec 12.5.
The backup would not compress. Symantec told us that Backupexec is capable of compression & HP told us that the tape drive is capable of compression. But we could not get any compression when used together.
An engineer in our firm did some digging around & came back saying that Symantec Backupexec will not support compression on USB Tape devices. We finally gave up & purchased a HP SAS DAT 160 & compression worked.
I am not looking for do this do that suggestions, trust me we have done it all. I am not concerned about how much compression & the factors that affect compression. As far as I am concerned 1MB over native capacity is compression
My question is does anybody (would love to hear from Symantec) know for a fact if it is still true for the latest version of Symantec Backupexec i.e. It will not support compression on USB Tape devices?
Symantec don't have drivers for a USB tape drive, and maybe that is where your issue lies.
It's probably got to do with the lack of throughput on the USB interface. You can try stopping the BE services and using NTbackup (if Windows Server 2003) with the USB device to see if you get any compression.
As a matter of interest, is compression selected natively on the USB drive, and have you tried either hardware or software compression?
1. have you tried either hardware or software compression?
Yes , we always select Hardware , if unavailble then software
2. is compression selected natively on the USB drive
If you mean in the proerties of the device in Backupexec then yes.
3. using NTbackup (if Windows Server 2003) with the USB device to see if you get any compression.
Do not recall, but do remember running some HP test , that confirmed compression on the device. If I am not mistaken the device comes bundled with a lowend backup application & if I reemeber correctly that would compress.