LTO 232 and LTT 4.0 - Compression algorithm

[Matz Edelholt]

Hi.

LTT v4.0 and the Assements Test generates this
on a server with LTO 232 drive connected.

HP LTO 232 device installed.
In the error log there are some warnings that says.

"""The drives hardware compression algorithm is currently switched off"""

Can I change the compression algoritm on the device with some command?

Or is this something that thje BackUp sw can change? Seems like the compression is off when I run backup tests...

Any help is much welcome.
Thanks / Matz

[Matz Edelholt]

Hi.

I have switched the compression OFF / ON in BackUp Exec sw, but it didnt have any effect when doing the LTT test.
How can I verify that the LTO drive got the compression enabled.

Thanks.
/ Matz

[David Ruska]

The drive default is to have compression enabled. It can be overridden by the host/appication which sends down a SCSI "Mode Select" commmand to set compression along with the desired tape density (typically).

If you power-cycle the drive, the compression setting should return to default.

Some backup software packages implement software compession, and will disable hardware compression (since it will not be able to compress the data any further).