Kind of backup with DAT

[Francisco Pereira]

When i execute the ioscan -fnC tape the command show me some devices, like /dev/rmt/0m, /dev/rmt/0mn, /dev/rmt/0mnb and others, i want know what is the diferents among theirs.

[Chris Wilshaw · Accepted solution]

0m is the "standard" device name

0mn is the no-rewind device, which can be used with some backup utilities (tar for example) to store files in multiple sessions on a tape

0mnb is the no-rewind device using berkeley compression

Full details of each device can be used with the lssf command

eg:

lssf /dev/rmt/0mn

stape card instance 4 SCSI target 0 SCSI LUN 0 at&t no rewind best density available at address 0/10/0/0.0.0 /dev/rmt/0mn

[A. Clay Stephenson]

The best description is found in the section 7 man pages for mt. Man 7 mt for details. Probably the most confusing is the Berkeley/AT&T sytle conventions. These have to do with how the tape is repositioned after a file is closed; the Berkeley style convention is generally thought to be the most sane.