Troubleshooting mt I/O error

[Mathew Ericson]

I am trying to connect a AutoLoader 1/9 DLT8000 Library to a H40 HP 28655A HP-PB Single-Ended SCSI.

All lights on the unit are ok including Single-Ended Yellow/Orange Termination Light (on Terminator)

Library is found by operating system (11.00) as shown below and can successfully be used to move tapes around using 'mc' command

Class I H/W Path Driver S/W State H/W Type Description
===================================================================
bc 0 root CLAIMED BUS_NEXUS
lan 0 16 fddi UNCLAIMED UNKNOWN HP J2157A - FDDI Interface
lan 1 24 fddi UNCLAIMED UNKNOWN HP J2157A - FDDI Interface
lan 2 28 btlan1 CLAIMED INTERFACE HP HP-PB 100 Base TX card
/dev/diag/lan2 /dev/ether2 /dev/lan2
ext_bus 1 32 scsi1 CLAIMED INTERFACE HP 28655A - SE SCSI ID=7
target 7 32.0 target CLAIMED DEVICE
spt 0 32.0.0 spt CLAIMED DEVICE HP C7145-8000
/dev/rmt/picker
target 8 32.1 target CLAIMED DEVICE
tape 2 32.1.0 tape2 CLAIMED DEVICE QUANTUM DLT8000
/dev/diag/rmt/c1t1d0 /dev/rmt/2mb /dev/rmt/2mnb /dev/rmt/c1t1d0BESTb /dev/rmt/c1t1d0BESTnb
/dev/rmt/2m /dev/rmt/2mn /dev/rmt/c1t1d0BEST /dev/rmt/c1t1d0BESTn
ext_bus 2 33 lpr2 CLAIMED INTERFACE HP 28655A - Parallel Interface
/dev/c2t0d0_lp /dev/diag/c2t0d0_lp
ext_bus 3 52 scsi1 CLAIMED INTERFACE HP 28655A - SE SCSI ID=7
target 3 52.0 target CLAIMED DEVICE
tape 1 52.0.0 tape2 CLAIMED DEVICE HP HP35480A
/dev/diag/rmt/c3t0d0 /dev/rmt/1mb /dev/rmt/1mnb /dev/rmt/c3t0d0BESTb /dev/rmt/c3t0d0BESTnb
/dev/rmt/1m /dev/rmt/1mn /dev/rmt/c3t0d0BEST /dev/rmt/c3t0d0BESTn
target 4 52.2 target CLAIMED DEVICE
disk 8 52.2.0 disc3 CLAIMED DEVICE TOSHIBA CD-ROM XM-3301TA
/dev/dsk/c3t2d0 /dev/floppy/c3t2d0 /dev/rdsk/c3t2d0 /dev/rfloppy/c3t2d0
target 5 52.5 target CLAIMED DEVICE
disk 9 52.5.0 disc3 CLAIMED DEVICE SEAGATE ST34502LW
/dev/dsk/c3t5d0 /dev/floppy/c3t5d0 /dev/rdsk/c3t5d0 /dev/rfloppy/c3t5d0
target 6 52.6 target CLAIMED DEVICE
disk 10 52.6.0 disc3 CLAIMED DEVICE HP C3010M1
/dev/dsk/c3t6d0 /dev/floppy/c3t6d0 /dev/rdsk/c3t6d0 /dev/rfloppy/c3t6d0
ext_bus 4 53 lpr2 CLAIMED INTERFACE HP 28655A - Parallel Interface
/dev/c4t0d0_lp /dev/diag/c4t0d0_lp
tty 0 56 mux2 CLAIMED INTERFACE MUX
/dev/diag/mux0 /dev/diag/tty0p13 /dev/diag/tty0p5 /dev/tty0p0 /dev/tty0p14 /dev/tty0p6
/dev/diag/tty0p0 /dev/diag/tty0p14 /dev/diag/tty0p6 /dev/tty0p1 /dev/tty0p15 /dev/tty0p7
/dev/diag/tty0p1 /dev/diag/tty0p15 /dev/diag/tty0p7 /dev/tty0p10 /dev/tty0p2 /dev/tty0p8
/dev/diag/tty0p10 /dev/diag/tty0p2 /dev/diag/tty0p8 /dev/tty0p11 /dev/tty0p3 /dev/tty0p9
/dev/diag/tty0p11 /dev/diag/tty0p3 /dev/diag/tty0p9 /dev/tty0p12 /dev/tty0p4
/dev/diag/tty0p12 /dev/diag/tty0p4 /dev/mux0 /dev/tty0p13 /dev/tty0p5
processor 0 62 processor CLAIMED PROCESSOR Processor
memory 0 63 memory CLAIMED MEMORY Memory

However 'mt' commands do now work - so I cannot read/write from drive:

# mc -p /dev/rmt/picker -rDS
DT_slot_1 FULL AH7413
ST_slot_1 EMPTY
ST_slot_2 EMPTY
ST_slot_3 FULL AH7493
ST_slot_4 EMPTY
ST_slot_5 FULL AH7495
ST_slot_6 FULL AF1276
ST_slot_7 FULL AH7388
ST_slot_8 FULL AH7403
ST_slot_9 EMPTY
# mt -t /dev/rmt/2m rewind
/dev/rmt/2m: I/O error

Any suggestions on how to troubleshoot further?

[Steven E. Protter]

Please check the consistency of the SCSI ID settings.

Then:

insf -e
ioscan -fnCtstape

or just

ioscan

See if we can get these babies claimed.

Also, is the stape driver in the kernel in an IN status.

If not get it to that state with sam kernel drivers, put the new kernel in production and let the box boot.

Then, try again.

SEP

[Mathew Ericson]

# ioscan -fnkC tape
Class I H/W Path Driver S/W State H/W Type Description
==============================================================
tape 2 32.1.0 tape2 CLAIMED DEVICE QUANTUM DLT8000
/dev/diag/rmt/c1t1d0 /dev/rmt/2mb /dev/rmt/2mnb /dev/rmt/c1t1d0BESTb /dev/rmt/c1t1d0BESTnb
/dev/rmt/2m /dev/rmt/2mn /dev/rmt/c1t1d0BEST /dev/rmt/c1t1d0BESTn
tape 1 52.0.0 tape2 CLAIMED DEVICE HP HP35480A
/dev/diag/rmt/c3t0d0 /dev/rmt/1mb /dev/rmt/1mnb /dev/rmt/c3t0d0BESTb /dev/rmt/c3t0d0BESTnb
/dev/rmt/1m /dev/rmt/1mn /dev/rmt/c3t0d0BEST /dev/rmt/c3t0d0BESTn
# ioscan -fnkC stape

nothing returned

looks like I am using a different driver. I will try inserting stape driver into the kernel but tape2 has been found and used for the device

[Michael Tully]

As well as adding 'stape' make sure you alos have 'schgr' and 'sctl'.

[Mathew Ericson]

Micheal is that correct? I am using a HP-PB NIO SE card - I thought that if the ext_bus driver is scsi1 (which it is in ioscan above) then I need to use the spt driver?

[A. Clay Stephenson]

You already have the correct driver for the SE-SCSI card but in the back of my mind I'm almost positive that I've seen somewhere that DLT7000/8000's are not supported under SE-SCSI on HP-UX. Even if the drive is supported, the performance is going to be absolutely horrible because the DLT8K is going to be starved for data. At best, it will write just a bit, rewind, and write some more --- taking about a 100X performance hit over a DLT that is fed fast enough to stream. Your performance will actually be better using a DDS drive because its data requirements are no so voracious.

You might be able to use a 28696 FWD/HVD controller in conjunction with an LVD/HVD SCSI bus translator but this seems like an awful lot of effort for an old H-box.

[Mathew Ericson]

I have had this drive connected to the SE interface on a A180 so it does work in SE. It is a LVDS library and can be connected LVD or SE.

It worked on the A180 but not on the H40?

[Mathew Ericson]

I should clarify that the unit is simply going to be used for validating some archive tapes before being moved to a L2000 (still on delivery)

Just want to validate the hardware configuration (the A180 was at another site before being shipped)

The unit comes with LVD and HVD configurations so my only option is LVD or SE at this stage - withour swapping out components.