Server 9000/800/K380: Daisy-chaining DLT 8000 & A3312A (jamaica) disk array

[Manuel Cotallo]

Hi,

We're trying to connect a external DLT 8000 drive to a K-series old system.

Our only possibility is to to daisy chain the DLT with the boot disk array at HW path 10/0(connected to core I/O F/W SCSI), as HP-PB board is damaged,with its fault LED blinking ...

Is it suitable this config? We were not able to make it work with array at SCSI target 6, and DLT at SCSI target 3, neither boot disk nor DLT were detected at boot time. Should we change target for DLT?
Another question, which will be the connections at the back of the jamaica array?

And a third question ... is it "Optional" connector at Core I/O board (HW path 10/8) suitable for SCSI devices, or is it only appropiate for graphics console as it says K-series owner guide?

Thanks a lot for any clue you can give,
Manuel Cotallo.


P.S.1
IOSCAN for HW PATH 10/0

H/W Path Class Description
=======================================
10/0 ext_bus GSC built-in Fast/Wide SCSI Interface
10/0.6 target
10/0.6.0 disk SEAGATE ST39236LC
10/0.7 target
10/0.7.0 ctl Initiator


P.S.2. EXTENDED IOSCAN:


ioscan -fn
Class I H/W Path Driver S/W State H/W Type Description
========================================================================
bc 0 root CLAIMED BUS_NEXUS
bc 1 8 ccio CLAIMED BUS_NEXUS I/O Adapter
ext_bus 0 8/8 c720 CLAIMED INTERFACE GSC add-on
Fast/Wide SCSI Interface
target 0 8/8.1 tgt CLAIMED DEVICE
disk 0 8/8.1.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c0t1d0 /dev/rdsk/c0t1d0
target 1 8/8.2 tgt CLAIMED DEVICE
disk 1 8/8.2.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c0t2d0 /dev/rdsk/c0t2d0
target 2 8/8.3 tgt CLAIMED DEVICE
disk 2 8/8.3.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c0t3d0 /dev/rdsk/c0t3d0
target 3 8/8.4 tgt CLAIMED DEVICE
disk 3 8/8.4.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c0t4d0 /dev/rdsk/c0t4d0
target 4 8/8.5 tgt CLAIMED DEVICE
disk 4 8/8.5.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c0t5d0 /dev/rdsk/c0t5d0
target 5 8/8.6 tgt CLAIMED DEVICE
disk 5 8/8.6.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c0t6d0 /dev/rdsk/c0t6d0
target 6 8/8.7 tgt CLAIMED DEVICE
ctl 0 8/8.7.0 sctl CLAIMED DEVICE Initiator
/dev/rscsi/c0t7d0
target 7 8/8.8 tgt CLAIMED DEVICE
disk 6 8/8.8.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c0t8d0 /dev/rdsk/c0t8d0
target 8 8/8.9 tgt CLAIMED DEVICE
disk 7 8/8.9.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c0t9d0 /dev/rdsk/c0t9d0
ext_bus 1 8/12 c720 CLAIMED INTERFACE GSC add-on
Fast/Wide
SCSI Interface
target 9 8/12.1 tgt CLAIMED DEVICE
disk 8 8/12.1.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c1t1d0 /dev/rdsk/c1t1d0
target 10 8/12.2 tgt CLAIMED DEVICE
disk 9 8/12.2.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c1t2d0 /dev/rdsk/c1t2d0
target 11 8/12.3 tgt CLAIMED DEVICE
disk 10 8/12.3.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c1t3d0 /dev/rdsk/c1t3d0
target 12 8/12.4 tgt CLAIMED DEVICE
disk 11 8/12.4.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c1t4d0 /dev/rdsk/c1t4d0
target 13 8/12.5 tgt CLAIMED DEVICE
disk 12 8/12.5.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c1t5d0 /dev/rdsk/c1t5d0
target 14 8/12.6 tgt CLAIMED DEVICE
disk 13 8/12.6.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c1t6d0 /dev/rdsk/c1t6d0
target 15 8/12.7 tgt CLAIMED DEVICE
ctl 1 8/12.7.0 sctl CLAIMED DEVICE Initiator
/dev/rscsi/c1t7d0
target 16 8/12.8 tgt CLAIMED DEVICE
disk 14 8/12.8.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c1t8d0 /dev/rdsk/c1t8d0
target 17 8/12.9 tgt CLAIMED DEVICE
disk 15 8/12.9.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c1t9d0 /dev/rdsk/c1t9d0
bc 2 10 ccio CLAIMED BUS_NEXUS I/O Adapter
ext_bus 2 10/0 c720 CLAIMED INTERFACE GSC built-in
Fast/Wide SCSI Interface
target 18 10/0.6 tgt CLAIMED DEVICE
disk 16 10/0.6.0 sdisk CLAIMED DEVICE SEAGATE
ST39236LC
/dev/dsk/c2t6d0 /dev/rdsk/c2t6d0
target 19 10/0.7 tgt CLAIMED DEVICE
ctl 2 10/0.7.0 sctl CLAIMED DEVICE Initiator
/dev/rscsi/c2t7d0
bc 3 10/4 bc CLAIMED BUS_NEXUS Bus Converter
tty 0 10/4/0 mux2 CLAIMED INTERFACE MUX
/dev/diag/mux0 /dev/diag/tty0p7 /dev/tty0p1
/dev/diag/tty0p0 /dev/mux0 /dev/tty0p7
/dev/diag/tty0p1 /dev/tty0p0
lan 0 10/4/8 btlan1 CLAIMED INTERFACE HP HP-PB 100
Base TX
card
ext_bus 3 10/8 c720 CLAIMED INTERFACE GSC add-on
Fast/Wide
SCSI Interface
target 20 10/8.7 tgt CLAIMED DEVICE
ctl 3 10/8.7.0 sctl CLAIMED DEVICE Initiator
/dev/rscsi/c3t7d0
ba 0 10/12 bus_adapter CLAIMED BUS_NEXUS Core I/O Adapter
ext_bus 5 10/12/0 CentIf CLAIMED INTERFACE Built-in
Parallel In
terface
/dev/c5t0d0_lp
ext_bus 4 10/12/5 c720 CLAIMED INTERFACE Built-in SCSI
target 21 10/12/5.0 tgt CLAIMED DEVICE
tape 1 10/12/5.0.0 stape CLAIMED DEVICE HP C1537A
/dev/rmt/1m /dev/rmt/c4t0d0BESTn
/dev/rmt/1mb /dev/rmt/c4t0d0BESTnb
/dev/rmt/1mn /dev/rmt/c4t0d0DDS
/dev/rmt/1mnb /dev/rmt/c4t0d0DDSb
/dev/rmt/c4t0d0BEST /dev/rmt/c4t0d0DDSn
/dev/rmt/c4t0d0BESTb /dev/rmt/c4t0d0DDSnb
target 22 10/12/5.2 tgt CLAIMED DEVICE
disk 17 10/12/5.2.0 sdisk CLAIMED DEVICE HP DVD-ROM
304
/dev/dsk/c4t2d0 /dev/rdsk/c4t2d0
target 23 10/12/5.7 tgt CLAIMED DEVICE
ctl 4 10/12/5.7.0 sctl CLAIMED DEVICE Initiator
/dev/rscsi/c4t7d0
lan 1 10/12/6 lan2 CLAIMED INTERFACE Built-in LAN
/dev/diag/lan1 /dev/ether1
ps2 0 10/12/7 ps2 CLAIMED INTERFACE Built-in
Keyboard/Mo
use
/dev/ps2_0 /dev/ps2kbd
/dev/ps2_1 /dev/ps2mouse
bc 4 10/16 bc CLAIMED BUS_NEXUS Bus Converter
ext_bus 6 10/16/4 scsi3 CLAIMED INTERFACE HP 28696A -
Fast/Wide SCSI Interface
processor 0 32 processor CLAIMED PROCESSOR Processor
memory 0 49 memory CLAIMED MEMORY Memory

[Andrew Rutter]

hi, is the dlt drive a FWD device? if it is then you should be able to daisy chain it on the jamaica box, but not ideal. You can get an optional scsi if for the core I/o 10/8 part number A2969A.
It doesnt matter which connector top or bottom you use on the hass box as its just a pass through. Make sure its properly terminated though. There is a top and bottom connector for each side of the hass box so it could be split into two if needed rather than use as one. The part number for a replacemnent HPPB i/f is 28696A which is lissted in the ioscan output. If its a single ended DLT then you will need another HPPB i/f Part number 28655A.
DLT drives are not always picked up on the older 9000's at PDC as they are not potential boot devices.
You will have to also make sure you have the relavent stape patches and kernal drivers installed to pick it up correctly, but should pick it up as unclaimed even if they are not present

hope thats of some use

Andy

[Manuel Cotallo]

Thanks a lot, Andrew ...

From what you say, I presume we already have the optional SCSI at path 10/8) ... as people told me the DLT was formerly connected at that point, after the HP-PB broke down ... and it worked ...


But now neither it works at 10/8 nor it does daisy chaining it at 10/0, so maybe we're having trouble with the DLT itself ... As far as i remember (although haven't got the part number here), the DLT was FW SCSI so there shouldn't be any compatibity issues ...

So I'm almost sure the DLT is damaged, but the only way to know it for sure will be by connecting it to other K system ... Think i'll try this ...

Thanks again for your interest and help,
Manuel Cotallo.

[Manuel Cotallo]

Anyway ...

what patches should be on the system (running HP-UX 11.00) for a FW DLT?

and what drivers should be activated (stape, tape2 ...) if we presume that the DLT is going to be attached externally to the GSC bus?

Thanx !
M. Cotallo.

[Tom Ward_1]

Putting tape devices and disk drives on the same SCSI bus is a bad thing. You are likely to have lbolts and even random crashes. I've never seen it work well.

Regards,
Tom

[Dave Unverhau_1]

Manuel,

Another concern with regard to sharing a FWD SCSI bus between a DLT8000 and *any* other device is that the DLT will saturate the bus. That is, in order to work properly, data must be provided to the drive fast eough to allow it to "stream" the data to the tape. On a FWD bus, this will demand the full bandwidth of the bus, and not allow for other activity.

If other i/o takes place while trying to stream data to the tape drive, the aforementioned SCSI LBOLT errors will likely occur, as well as premature wear of the tape mech, due to excessive repositioning operations when the tape buffer has insufficient data to sustain streaming.

Bottom line: find a dedicated FWD channel for that DLT8000.

Best Regards,

Dave

[Alexander M. Ermes]

Hi there.
Just my 2 ct.
I would suggest, you connect the DLT tape drive to a separate SCSI interface.
The speed advantage of the DLT will be lost, if you daisychain it with something else.
The tapedrive will not go into streaming mode, that means it will wind and rewind the tape during the usage instead of one continous wind, because the bus cannot deliver the necessary amount of data.
Rgds
Alexander M. Ermes