DLT4 compression

[David Vincent]

I want to compress the data when i'm doing a backup but the compression light always light off. But when i passed the Hp tools the 2:1, 3:1 and 4:1 compression test pass. I use windows 2000 and the windows 2000 backup software

thanks

[Eugeny Brychkov]

If there's no button on the tape drive to turn compression on then try doing it with backup utility:
ntbackup /hc:on
Eugeny

[David Vincent]

yes there's a button...the compression light is on, but when the backup start the light goes OFF

[Eugeny Brychkov]

Then explore your backup application to find out where to set it not to disable compression!
Although this application could be so clever to turn off compression for backing up already compressed files... But if it's windows NT backup then use this key '/hc:on'
Eugeny

[GK_5]

Is it a brand new tape or tape used in other drive or by other software. Sometime if tape is used in other drive or software the new drive/software can not recognize the old format and ignores the compression. I have seen it in Veritas Netbackup.