Tape device file does not exist

Question

I am trying to Read / Write data into my HP LTO3 1X8 Autoloader Tape drive. I have the required drivers installed.

When I ran rpm -qa | grep mt-st I got:

mt-st-1.1-5.el6.x86_64

Further when I ran cat /proc/scsi/scsi I got:

Host: scsi1 Channel: 00 Id: 00 Lun: 00
  Vendor: NECVMWar Model: VMware IDE CDR10 Rev: 1.00
  Type:   CD-ROM                           ANSI  SCSI revision: 05
Host: scsi2 Channel: 00 Id: 00 Lun: 00
  Vendor: VMware   Model: Virtual disk     Rev: 1.0
  Type:   Direct-Access                    ANSI  SCSI revision: 02
Host: scsi2 Channel: 00 Id: 01 Lun: 00
  Vendor: HP       Model: 1x8 autoloader   Rev: 1.50
  Type:   Medium Changer                   ANSI  SCSI revision: 03

Further tapeinfo -f /dev/sg2:

Product Type: Medium Changer
Vendor ID: 'HP      '
Product ID: '1x8 autoloader  '
Revision: '1.50'
Attached Changer API: No
SerialNumber: 'MXA0633052'
SCSI ID: 1
SCSI LUN: 0
Ready: yes

There is no device file st0 in my /dev location. So I tried to make it by some references from internet.

I ran mknod /dev/st0 c 9 0, but when I use mt command

mt -f /dev/st0 status

/dev/st0: No such device or address

Please point me in right direction

Solution

Vendor: VMware Model: Virtual disk says you're running a VM. As such, it is entirely possible you aren't seeing the tape device because it isn't exported to your VM. You have the library mapped, but not the drive within it -- which is a free-standing SCSI device.

(or, perhaps your library is missing its drive???)

Comments

[yoonix]

Have you gone through this doc? HP StorageWorks Tape Autoloaders - Troubleshooting HP StorageWorks Autoloaders in Linux

[Hisibut1960]

@yoonix I tried but i can't see the tape device file, frep returns nothing to me

[Hisibut1960]

I ran those commands you mentioned, but non of them returned me anything,except mtx -f /dev/sg2 status

[slm]

@shadow - has the system been rebooted recently or been up for a long time? The contents of dmesg get's dropped over time, so to really confirm those commands a reboot would be needed.

[slm]

@shadow - there was no mention of any of the tape devices in dmesg. Perhaps the pattern I'm telling you to grep for is incorrect for your particular hardware. If nothing is showing up there, then that tells me that the Linux kernel is not detecting this hardware correctly. I would also take a look in your system's BIOS for potential leads too.

[Hisibut1960]

When i ran mtx -f /dev/sg2 status it showed me different storage elements

[slm]

@shadow - it should not matter if the tapes been formatted or not, the example shows a unformatted tape, so something else would seem to still be the underlying issue.

[Hisibut1960]

In my base system it is vmware and VM mounted on it is running centOS