Incorrect Tape device/description

[Nick Wickens]

I have just re-connected a DLT7000 718 2/8 changer onto a K class under 10.20 that was originally on that machine as /dev/rmt/2m. However on reconnection its picked up an instance number of 8 and a device name of /dev/rmt/8m. The autochanger device is still working fine under Omniback 3.5 but if I try and scan the drive as 8m I get an I/O error. I don't think that the ioscan (below) description is right for this drive (normally quantum as I recall). Any ideas for getting it back to 2m without a reboot - I have tried removing and recreating the /dev/rmt files with insf but still it comes back as 8m I quess because of the instance number ?

tape 8 10/16/8.3.0 tape2 CLAIMED DEVICE DT00 C6280-7000
/dev/diag/rmt/c6t3d0 /dev/rmt/c6t3d0BEST
/dev/rmt/8m /dev/rmt/c6t3d0BESTb
/dev/rmt/8mb /dev/rmt/c6t3d0BESTn
/dev/rmt/8mn /dev/rmt/c6t3d0BESTnb
/dev/rmt/8mnb

[Pete Randall]

Nick,

As long as there are no conflicts with other device files you can use this procedure to recreate them with whatever name you desire:


1. Use "ioscan" to find out what the current device files look like and what the instance number is:
ioscan -kfnCtape


2. Use "mksf" to create each of the four types of device files:

/sbin/mksf -d stape -I 12 -a -b BEST rmt/12m
/sbin/mksf -d stape -I 12 -u -b BEST rmt/12mb
/sbin/mksf -d stape -I 12 -a -n -b BEST rmt/12mn
/sbin/mksf -d stape -I 12 -u -n -b BEST rmt/12mnb


3. Use "ll" to compare your newly created device files with those created by the system. Major and minor
numbers should match between corresponding entries (205 0x061000 for both 12m and the equivalent c6t1d0BE
ST):

ll /dev/rmt |more

crw-rw-rw 1 bin bin 205 0x061000 Mar 17 08:40 12m
.
.
.
crw-rw-rw 1 bin bin 205 0x061000 Mar 17 08:40 c6t1d0BEST
.
.
.



4. repeat the ioscan to double check that your new device files are associated with the correct tape driv
e:

ioscan -kfnCtape



I was using 12m in the example but you can use anything you want.



Hope this helps!


Pete

[Massimo Bianchi]

Can you issue an

lssf /dev/rmt/c6t3d0BEST

I think that this is due to some history in the adding of the tapes.

You can force the binding with ioscan and insf, but this can cause some problem later, so i think that is best to make it work now with the new config.

The instance number usually is involved in the name of the special files, your guess is right.

Massimo

[Helen French]

Normally the device file name changes when you change the SCSI ID while reconnecting. Check this and if possible, set it back to it's original SCSI ID.

Also, you can create your own /dev/rmt/2m with 'mknod' command. What you have to do is find out the major number (ls -la /dev/rmt/8m) and the minor number (ioscan -fn).

# mknod /dev/rmt/XXX c major minor

[Nick Wickens]

Thanks for the replies peoples - Looking back at some old ioscans I have confirmed that the device used to show as a QUANTUM DLT7000 but now shows as DT00 C6280-7000. Omniback is not listing at as an available drive and if I force omniback to use the /dev/rmt/8m device the tape gets loaded but an attempted scan comes back with "Can not open device ([5]I/O error)".

lssf for device shows -
tape2 card instance 6 SCSI target 3 SCSI LUN 0 at&t best density available at ad
dress 10/16/8.3.0 /dev/rmt/c6t3d0BEST
lssf /dev/rmt/8m
tape2 card instance 6 SCSI target 3 SCSI LUN 0 at&t best density available at ad
dress 10/16/8.3.0 /dev/rmt/8m

[Massimo Bianchi]

10/16/8.3.0 /dev/rmt/c6t3d0BEST


Yes, something is dirty

device file name should be c8t3d0, but maybe that some other equipment stole that address in the past.


If rmsf -H do not work, i think that the only way to get it clean is:

- find how why the description string has changed
- clear it all and have a reboot (this will clean entry in ioconfig)
- shudown -h, put the tape in and then reboot another time

Massimo