Dear all,

I just learn to use Linux for 3 months. My PC is running:

- Pentium II 400Mhz
- 192MB memory
- Adaptec 2940UW SCSI card
- HP DAT24 (24GB) tape drive - DDS3
- Linux: Fedora Core 2

My problem is:
when I type "mt -f /dev/st0 status", it respond "/dev/st0: No such device or address."

but I am sure the hardware is installed properly because I had tried it with another Windows 2000 harddisk(I am using a removable HDD rack) at same machine.

I also used "tar -cf /dev/st0 test --verify", it shows following:
"tar: /dev/st0: Cannot open:
tar: Error is not recoverable: Exiting now"

Can anybody help me?

Do you have the st.o module loaded. Try looking in the dmesg output for errors also.
Also check the output of lsmod.
Does 'cdrecord -scanbus' detect the DDS3 unit?

Thank you, jschiwal.

'dmesg' is the first command I learn here.

I use "dmesg" to check messages. It seems ok.

I can open my Linux PC to all experts here, can anybody use Telnet to login and then tell me whats the problem there?
Commands to login my PC:
==================
telnet 219.76.223.35
mike (login
bbc1234 (password
su root (switch to root)
bbc1234 (password
==================

I have a tape inserted already.

thanks

I have a similar problem.
I am running RH.9 on a Compaq 370 Proliant.
Have you had any luck with this?

Please change you password and stop using the telnet service. Making you password public is very dangerous. Any hacker can take control of you machine.

Also, the telnet protocol sends the user-name and password over the net in the clear. Use the secure shell instead. The secure shell (ssh) is probably already installed on your machine, but you may need to generate a secret key. Look in man ssh for details.

Back to your problem. We need to find out why there isn't a st0 device. Does this tape device have rewind? What mode does it use? These could result in a different device name being used. (Without rewind, the device name starts with /dev/nst ). Please refer to the SCSI Howto PDF I've referenced at the bottom of this message for details.

The cdrecord command is normally used when setting up cdroms, however we will use it to show if the device is being detected on the scsi bus.

Show us the output of this command as well as the output of the 'lsmod' command. The lsmod command will show us which kernel modules are loaded.

The 'modprobe' command will scan for a type of device and load in the proper module for the device that is found. Sometimes a kernel module for a particular device needs to be compiled, however for a scsi tape drive a generic device probably will do. However, there are scsi drivers that need to be supported by the kernel either as loadable modules, or compiled in the kernel. There are lower level scsi drivers that higher level drivers depend on. Support for these drivers needs to be selected when the kernel is compiled. For scsi that is probably the case already (however I don't have fedora2)

Please let us know which kernel version you are using. A 2.4 kernel or a 2.6 kernel.

Also the driver for the scsi controller needs to be included.

Look at the output of: 'cat /proc/scsi/scsi'
This should list the scsi devices in the system.
Also look at the output of 'cat /proc/scsi/sg/device_strs'
This list should show the Manufacturer Model and Version number of the device detected by the sg.o driver.

The solution may be as simple as adding an entry to the /etc/modules.conf file so that the modules are loaded during the boot process.

Does the drive have a switch for changing the lun number. Device 7 is usually used for the scsi controller card itself. Try numbers on both sides of '7', like 5 and 9. I remember installing scsi drives on a computer at work and moving the lun number on the other side of 7 was needed before the adaptor functioned properly. This is a long shot but maybe worth a try.

The tape driver interface (st) is documented in the file /usr/src/linux/drivers/scsi/README.st and on man 4 st.

Lastly, here is a pdf SCSI HowTo for the 2.4 kernel.
http://www.ibiblio.org/pub/Linux/doc...-2.4-HOWTO.pdf
Well good luck.

I am using a 2.6.5 kernel

thanks, jschiwal.
after i type 'lsmod', the following display:
========================================
Module Size Used by
parport_pc 19392 1
lp 8236 0
parport 29640 2 parport_pc,lp
autofs4 10624 0
rfcomm 27164 0
l2cap 16004 5 rfcomm
bluetooth 33636 4 rfcomm,l2cap
sunrpc 101064 1
3c59x 30376 0
floppy 47440 0
sg 27552 0
st 31132 0
scsi_mod 91344 2 sg,st
microcode 4768 0
dm_mod 33184 0
uhci_hcd 23708 0
ipv6 184288 12
ext3 102376 2
jbd 40216 1 ext3
========================================

Actually, I don't know what the above message means. Can u see anything wrong.

You have the modules sg, st and scsi_mod.
Could you provide the cat listing of /proc/scsi/scsi
and /proc/scsi/sg/device_strs to see if you device is connected.

'cat /proc/scsi/scsi', it shows:
Attached devices:

when i type 'cat /proc/scsi/sg/device_strs'
i got nothing.

The SCSI tape module is loading but not the SCSI controller module which is the reason your not seeing any SCSI devices with the cat command. I assume you did not compile the controller module into the kernel.

To load the module as root:
modprobe aic7xxx

i use 'modprobe aic7xxx'. it seems workable.

thank you all.