HP SureStore DLT1

[CA735626]

How to enable hardware compression of DLT1?
It is connected to a Netware 5 Server.

Thanks in advance.

Joshua

[CA713937]

Unlike most DAT drives, there are no physical configuration switches on the DLT1 (or DLT) drives to control compression. Thus, compression must be controlled by software.

For SCSI tape drives, the compression is controlled through the Mode Select command, with either the density code field, or parameters in either the control mode page (0Ah) and/or the data compression page (0Fh). The good news is you don't need to know the specifics of this - the device driver takes care of it.

The way the device driver is told to control compression varies by OS. For unix, this is typically done by unique device files that enable or disable compression, or with a utility like "mt" [or "tape" on solaris]). For windows systems (and I would guess also for Netware), you don't have unix-like device files, so compression would need to be controlled by your backup application.

For an application like Veritas Backup Exec on Netware, compression is controlled under the "Drive Properties" dialog, on the "configuration" tab. A "compression method" field can be set to HARDWARE, SOFTWARE, or NONE. When set to HARDWARE, the drive's compression functionality is enabled.

Hope this information helps.

[CA735626]

Thank you very much, David.
However, we are using ArcserveIT6.6 for Netware.
I have enabled Compression option through Device Management of Arcserve. It seems doesn't work. I am wondering is there a switch or jumper setting in this tape drive? Thanks.

Joshua

[CA735626]

I have got the answer. Hardware compression default is enabled for HP DLT1.
Thanks.