ultrium 230 tape drive on rhel 3

[Sunil Kumar K.U.]

Hello,

i have a proliant server DL380 G4 running Red Hat Linux Advanced Server Version-3 update-4. There is a HP Storageworks Ultrium230 tape drive connected to the External connector of the Smart Array-6i controller. It is observed that during boot up the array controller BIOS detects this Tape drive at SCSI ID-3.

But the OS doesn't sense this drive. I couldn't find any drivers available for this drive on the net. Anybody here faced similar issue? or anybody has a working system with similar setup? Any help will be appreciated.

Thanks and Best regards,
Sunil Kumar

[Stuart Browne]

You don't need any extra drivers, the drive will be supported by the OS as is.

What you need to do though is to force the SA6i to tell the OS that the tape is there.

Because the SA6i is a RAID controller, it needs a bit of a poke to make it show up in a recognizable fashion.

Start by reading '/usr/share/doc/kernel-doc-*/cciss.txt'. It outline's everything, and has a good discussion on why it's needed.

The short/simple answer is to try this:

for x in /proc/driver/cciss/cciss[0-9]*
do
echo "engage scsi" > $x
done

From there, you should see a 'Sequential Access' device listed in '/proc/scsi/scsi', and should be able to 'modprobe st' and use '/dev/st0' & '/dev/nst0'.

[Bejoy C Alias]

Can u paste the portion of the dmesg where the message for drive and scsi card detection comes

[Sunil Kumar K.U.]

Hello,

Thanks Stuart for the quick reply. As you said I shall execute the commands. Is this step required only once or do we need to do it after every reboot?

Let me try this step and get back.

Bejoy: As I said before, the OS doesn't recognise the tape drive, therefore there are no entries for it in dmesg output.

Thanks and Best Regards,
Sunil Kumar

[Stuart Browne]

I'd assume at every boot (add those lines to '/etc/rc.d/rc.local'), but I don't have a system which has that issue ;)

Every SA-based machine with an attached tape drive I've used has never exhibited this issue ;)

Go figure.

I just know the answer 'cause it's been a question that has shown up fairly reguarly recently, combined with I did a fair bit of research into using tape drives on SA's for my previous employer.

(Oh, and I'm a freak who just reads for the hell of it! Should read the kernel VM stuff :P funky stuff! *nod*).

[Sunil Kumar K.U.]

Hello Stuart,

Thanks for the help. There was /proc/driver/cciss/cciss0 in my system and I gave echo "engage scsi" > /proc/driver/cciss/cciss0 . After that the tape drive was accessible at /dev/st0.

Also, I found that the tape drive was inaccesible after a reboot. I had to put an entry in /etc/rc.d/rc.local, as you had mentioned.

As the problem is sorted out, could you pls tell me what kind of magic this echo command is doing so that the SA start detecting the tape drive?

Thanks and Best Regards,
Sunil Kumar

[Stuart Browne · Accepted solution]

As the SA is a RAID controller, normally it just presents the containers to the OS as SCSI disks, and no other devices.

Sending the 'engage scsi' to the SA forces it to show other possible SCSI devices as well (from my understanding of the documentation at least).

[Sunil Kumar K.U.]

Hello Stuart,

Thanks for the help. Let me close this thread as the pblm is sorted out.

Thanks and Best Regards,
Sunil Kumar K.U.

[Sunil Kumar K.U.]

The discssion was useful in solving the pblm.