In a message dated: Thu, 01 Nov 2001 18:16:40 EST Benjamin Scott said:
>List, > > Does anyone here know how to tell a Quantum DLT 7000 SCSI tape drive to >turn on hardware compression under Linux (for use with "tar" and the like)? >I have tried "mt compression 1" and "mt setdensity 0x85" and "mt defdensity >0x85", but none of them seem to have any affect. At least, they do not >appear to. It takes the same amount of time and same number of tapes to >backup the same data set, regardless of settings. I would imagine *some* >variation with compression turned on, even if the data does not compress >well (indeed, in that case, it is supposed to take *longer*). > > The drive is inside a tape changer, so looking at the front-panel LEDs is >difficult. :-) > > I am hoping someone here has played around with hardware data compression >under Linux before. Or under any Unix, for that matter. Information on >this is proving scarce. What model changer is it? Also, make sure that you have the SCSI generic driver compiled in, you need to access /dev/sgX. You don't want to use hw compression, it's not that great, and often times increases the size of your backup set. Use sw compression like gzip with tar. Let me know if you're using amanda. ***************************************************************** To unsubscribe from this list, send mail to [EMAIL PROTECTED] with the text 'unsubscribe gnhlug' in the message body. *****************************************************************
