SCSI Tape/Library Problem

[Andrew Mathews]

Brett I. Holcomb wrote:
> I have a Cybernetics tape library (SCSI) with tape drive (also SCSI).  I'm attempting to test it with simple commands like tar -cvf /dev/tape0 /somedir.  This gives a list of files ,then "write 0 of 1024 blocks, error not recoverable"
> 
> If i use mt -f /dev/tape0 status I get "operation not permitted).
> 
> The tape device (see cat /proc/scsi/scsi below) is id 0 on host 1 while the library is ID 1 on host 1.  The /dev/sg1 is linked (by gentoo) to the /scsi device so I created a link /dev/tape0 to /dev/sg1.

BZZT! Remove this and link it to /dev/st0 not sg0.

> 
> lr-xr-xr-x    1 root     root           36 Jan 14 10:01 /dev/sg1 ->scsi/host1/bus0/target0/lun0/generic
> 
> Why does mt tell me the operation is not allowed?  The /scsi entries have the correct permissions.  I'm doing this as root - any ideas?
> This system is using the devfs file system. 
> 
<snip>
Because you can't get the status of the changer, (sg0) you can only get 
the status of the drive (st0). Remember that with a library, you'll have 
2 devices, the tape drive (st0) and the changer (sg0). I wrote a backup 
script for an ADIC 7 tape DLT library that uses tape 1 for Sunday, tape 
2 for Monday, etc. if you'd like. (it uses xfsdump, you'll need to 
modify it for tar, cpio, or dump)

-- 
Andrew Mathews
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