Cannot Open /dev/st0

[Elizangela Fernandes]

Hi,

I`m use Red Hat 2.1 Enterprise and connect the new tape device, a Dell tape Device.

When I try backup with tar, the message appear:

tar: /dev/st0: Cannot open: No such device
tar: Error is not recoverable: exiting now

The file permissions:
crw-rw---- 1 root disk 9, 0 Mar 19 2002 /dev/st0

Dmesg is atached

I execute

depmod
modprobe st

and

depmod -a
modprobe aic7xxx

but the same message appear.

Can anyone help me please.

My server don`t have backup.

[Slawomir Gora]

Hi,

in your dmesg output there is no info about
tape (st) driver.

show me output commands:
1. cat /proc/scsi/scsi
2. lsmod

[Stuart Fuller_2]

The dmesg output does not indicate that a tape drive was found.

What kind of a Dell tape device is this? Is it SCSI?

[Elizangela Fernandes]

Atacched proc/scsi

Model is a Dell Super DLT 320 Power Volt 110T.

[root@soaapp03p root]# lsmod
Module Size Used by Not tainted
vfat 13244 0 (autoclean)
fat 40408 0 (autoclean) [vfat]
ide-tape 61120 0 (autoclean)
sr_mod 17592 0 (autoclean) (unused)
cdrom 35520 0 (autoclean) [sr_mod]
st 30548 0 (autoclean) (unused)
tg3 50496 1
usb-ohci 23456 0 (unused)
usbcore 68896 1 [usb-ohci]
ext3 71264 6
jbd 55636 6 [ext3]
aic7xxx 127200 0
aacraid 34516 8
sd_mod 13856 8
scsi_mod 127292 5 [sr_mod st aic7xxx aacraid sd_mod]


Thanks

[Slawomir Gora]

Hi,

one more file
cat /proc/scsi/scsi

[Elizangela Fernandes]

[root@soaapp03p root]# cat /proc/scsi/scsi
Attached devices:
Host: scsi0 Channel: 00 Id: 00 Lun: 00
Vendor: DELL Model: PERCRAID Mirror Rev: V1.0
Type: Direct-Access ANSI SCSI revision: 02

Thank's

[Slawomir Gora]

Hi,
your system doesn't see tape drive - no entry in /proc/scsi/scsi.
Is your tape recognized by SCSI Adapter BIOS during system startup ?
Maby you have hardware problem -check cable, terminator if needed.

[Elizangela Fernandes]

Sorry,

I`m new user in Linux.

I checked cables and the terminator is OK.

The Tape is a LVD. This tape work ok at a windows system

Dell said that the drive was at System Kernel.

[Stuart Browne]

Did you plut the tape drive in whilst the machine was up?

Or have you since power-cycled/rebooted the server?

You may need to get the SCSI subsystem to rescan the SCSI bus'.

[Eric van Dijken]

Can you see the Tape drive, when you enter the Adaptec bios menu?

If it doens't show there, no matter what you do on Linux level will activate your tape drive. But it will tell that you have a hardware problem, not a Linux problem.

Once you fix that, i am sure your tape drive on Linux will work just fine.

[Elizangela Fernandes]

I don`t reboot the server . It's necessary. Sorry because in the HP-UX don`t need.

Thank`s.

I don`t know what do.

[Stuart Browne]

If you can't reboot the server, and it's plugged into one of the Adaptec SCSI controllers, then try getting the SCSI bus to re-scan it's self.

There was a post a few days ago with hot-swap drives, which lists how to do it.

[Gopi Sekar]

I had the same problem earlier on. Linux could not able to detect the external tape drives (for that matter any external connected devices) reliably.

You have two choices: Reboot the server and keep the tape drive powered on when the system boots up, so when kernel scans the SCSI bus it will detect the tape drive. If kernel detects the tape drive then dmesg output will list st0 or nst0 entries

Another not so reliable method is to power on the tape drive and ask the kernel to rescan the SCSI bus. Check the below link on how to accomplish this.
http://www.whoopis.com/howtos/tapebackup.html

Hope this helps,
Gopi

[Elizangela Fernandes]

Hi people,

Sorry but I rebooted my server yesterday and the problem continue.

How Can I get the tape drive model for put in the startup?

Anybody help me?

Thanks

[Stuart Browne]

When the system boots, prior to the OS or disks even being touched (i.e. in the BIOS phase), you should see each SCSI controller initialize.

It has a big banner saying "Adaptec ...". These will be followed by some lines which start with a number between 1 and 16.

At least one of them should be your tape drive.

Reboot the server while watching the screen. Use the 'Pause' key on the keyboard to hold the display whilst you write the details down.

Come back with that info.

Also, once the machine is booted, grab the contents of '/proc/scsi/scsi' too.

Post back with the details.

[Chris_815]

I have the same problem, well I get the error message:

./staging/
./staging/jitsicpdc
tar: /dev/st0: Wrote only 0 of 10240 bytes
tar: Error is not recoverable: exiting now

My tape drive is detected: (/proc/scsi/scsi)

Attached devices:
Host: scsi1 Channel: 00 Id: 03 Lun: 00
Vendor: HP Model: Ultrium 2-SCSI Rev: F48D
Type: Sequential-Access ANSI SCSI revision: 03

and the modules are loaded (lsmod)

Module Size
loop 8496
vmnixmod 201952
bcm5700 79428
st 25940

so it is being loaded... same message.
tar: /dev/st0: Wrote only 0 of 10240 bytes
tar: Error is not recoverable: exiting now
Any ideas?

[Roderik Hamers]

/dev/ cannot be contacted directly, just mount it before you use it. "mkdir /mnt/tapedrive; mount /dev/st0 /mnt/tapedrive/"

To start the tape drive in the beginning use your /etc/fstab

[Ivan Ferreira]

Tape devices doesnt have to be mounted!

You can force a SCSI detection without rebooting the server using the rescan-scsi-bus.sh script:

www.garloff.de/kurt/linux/rescan-scsi-bus.sh

If you still have the "No such device" error, then your device is not being detected.