Bingo! My Linux programmer was using the GNU mt command, which evidently was setting compression off. He switched to mtst and provided the compression operand and it works fine now. Thanks much, I'll keep this note in my "Linux/VM Compatibility" folder for future reference! :) -Mike
-----Original Message----- From: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] On Behalf Of Rempel, Horst Sent: Thursday, September 06, 2007 9:59 AM To: [email protected] Subject: AW: 3590 (B1A) Hardware Compression Hello Michael, you must install the mtst command in your Linux. After that you can enable the hardwarecompression (as far as I know the dafault is OFF) # mtst -f /dev/rtibm0 compression 1 This helped in my environment(Suse sles9) kindest regards Mit freundlichen Grüßen, Horst Rempel Berufsgenossenschaft http://www.bgchemie.de <http://www.bgchemie.de/> der chemischen Industrie e-mail [EMAIL PROTECTED] Abteilung EDV/DV-ORG Kurfürstenanlage 62 69115 Heidelberg Tel.: 06221 / 523-1303 Fax : 06221 / 523-227 -----Ursprüngliche Nachricht----- Von: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] Auftrag von Michael Coffin Gesendet: Donnerstag, 6. September 2007 15:14 An: [email protected] Betreff: 3590 (B1A) Hardware Compression We use 3590 B1A drives, with 10/30 carts providing native capacity of 10GB, with up to 30GB using hardware compression. I am under the impression that the hardware will choose the best compression possible UNLESS it is specifically told otherwise (i.e. via a TAPE COMP/NOCOMP and DDR COMP/NOCOMP/LZCOMP options). Is this true, and is there a way to query the hardware from z/VM (4.4) to see if default hardware compression has been enabled on the drives (I imagine it has to be set by the CE during install/configuration)? I have a z/Linux user that was trying to dump 13GB of data and ran out of space, so it looks as though default hardware compression is not working. :( -Mike
