Debian won't see a DLT Tape Library

evank · 10-13-2005, 10:33 AM

I've got a Dell PowerEdge server running a custom debian linux install (http://wiki.osuosl.org/display/LNX/D...n+Dell+Servers) and i'm attempting to get the OS to recognize a SCSI connected Compaq C5151C DLT Library (a.k.a tape autoloader a.k.a robot) for backup use.

naturally, i can locate no trace of the library on compaq/hp's website, apparently when they merged, they simply discarded support docs for certain products.

the server itself recognizes the DLT, as it indicates this during POST. as well, a knoppix live cd recognizes it as /dev/st0. past the LILO screen and into debian, however, the DLT is nowhere to be found:

Code:

$ ls /dev/st*
crw-rw----  1 root tape 9,  0 Mar 14  2002 /dev/st0
crw-rw----  1 root tape 9, 96 Mar 14  2002 /dev/st0a
crw-rw----  1 root tape 9, 32 Mar 14  2002 /dev/st0l
crw-rw----  1 root tape 9, 64 Mar 14  2002 /dev/st0m
crw-rw----  1 root tape 9,  1 Mar 14  2002 /dev/st1
crw-rw----  1 root tape 9, 97 Mar 14  2002 /dev/st1a
crw-rw----  1 root tape 9, 33 Mar 14  2002 /dev/st1l
crw-rw----  1 root tape 9, 65 Mar 14  2002 /dev/st1m
$ ls /dev/nst*
crw-rw----  1 root tape 9, 128 Mar 14  2002 /dev/nst0
crw-rw----  1 root tape 9, 224 Mar 14  2002 /dev/nst0a
crw-rw----  1 root tape 9, 160 Mar 14  2002 /dev/nst0l
crw-rw----  1 root tape 9, 192 Mar 14  2002 /dev/nst0m
crw-rw----  1 root tape 9, 129 Mar 14  2002 /dev/nst1
crw-rw----  1 root tape 9, 225 Mar 14  2002 /dev/nst1a
crw-rw----  1 root tape 9, 161 Mar 14  2002 /dev/nst1l
crw-rw----  1 root tape 9, 193 Mar 14  2002 /dev/nst1m

anything i try to do with the listed entries under /dev (after 'su'-ing to root) gives me a "No such device" error.

i tried a "modprobe st", and got an error that it can't locate a module named st.

i really dont know where to go from here, and if anyone could help or point me in the right direction, i would appreciate it.

MensaWater · 10-13-2005, 10:54 AM

Do you actually have a tape in the drive? A lot of times you get no such device with the mt command options if there is no tape mounted.

evank · 10-13-2005, 11:46 AM

there's no tape in the drive, no. and I can't load one because i'd have to issue a command to the robot to load a tape, and the robot is what debian doesnt seem to see.

MensaWater · 10-13-2005, 12:17 PM

OK - I'm not familiar with this robot. Most of the ones I've used have front panels that will allow you to move tapes in or out.

Doing a quick google for "Compaq C5151C" I do see forums on itrc.hp.com (HP's official forum site) discussing the device. Unfortunately the first one confirms that HP lost the documentation during the merger. Anyway searching on itrc.hp.com may be worthwhile even if it doesn't talk specifcally about Linux.

evank · 10-13-2005, 12:33 PM

yeah, it doesnt have a "mailslot" to add and remove tapes, and the drive itself i'm guessing is waaaaaay in the back of the cabinet.

at the advice of someone else, I took a peek at ALL the scsi devices connected:

Code:

Host: scsi1 Channel: 00 Id: 04 Lun: 00
  Vendor: HP       Model: C5151-2000       Rev: 2.06
  Type:   Medium Changer                   ANSI SCSI revision: 02

Host: scsi1 Channel: 00 Id: 05 Lun: 00
  Vendor: DEC      Model: DLT2000 CPQ LDRV Rev: 8626
  Type:   Sequential-Access                ANSI SCSI revision: 02

Host: scsi3 Channel: 00 Id: 06 Lun: 00
  Vendor: Quantum  Model: DLT4000          Rev: CD50
  Type:   Sequential-Access                ANSI SCSI revision: 02

i think the first device is the robot itself, and the second is possibly the drive contained in it. the third, i believe, is a single tape drive that is physically part of the server, and is in no way associated with the robot.

Wells · 10-14-2005, 03:24 PM

The third is a seperate tape drive. Note that it is on scsi3, which is a different scsi chain than the first two. The scsi1chan0id4 device is definately the changer (it says so), and the second one is probably the tape drive that is in the device. To control the hardware, you might want to give BRU (http://www.tolisgroup.com) a try and see if it detects the changer for the drive.

Quote:

Originally posted by evank
yeah, it doesnt have a "mailslot" to add and remove tapes, and the drive itself i'm guessing is waaaaaay in the back of the cabinet.

at the advice of someone else, I took a peek at ALL the scsi devices connected:

Code:

Host: scsi1 Channel: 00 Id: 04 Lun: 00 Vendor: HP Model: C5151-2000 Rev: 2.06 Type: Medium Changer ANSI SCSI revision: 02 Host: scsi1 Channel: 00 Id: 05 Lun: 00 Vendor: DEC Model: DLT2000 CPQ LDRV Rev: 8626 Type: Sequential-Access ANSI SCSI revision: 02 Host: scsi3 Channel: 00 Id: 06 Lun: 00 Vendor: Quantum Model: DLT4000 Rev: CD50 Type: Sequential-Access ANSI SCSI revision: 02

i think the first device is the robot itself, and the second is possibly the drive contained in it. the third, i believe, is a single tape drive that is physically part of the server, and is in no way associated with the robot.

evank · 10-14-2005, 05:34 PM

actually, I'm trying to get it recognized so I can use it with BRU. I'm going to try upgrading the kernel from 2.4.31 to 2.6, i think that ought to fix the problem. and if it doesnt, at least i'll know it doesnt have to do with kernel support for it.