topic Re: EXTERNAL SCSI- DISK FOR HPUX in Disk Enclosures

EXTERNAL SCSI- DISK FOR HPUX

Ajay_5 — Mon, 24 Sep 2001 04:28:46 GMT

Hi,
I am connecting a single scsi- disk [ST39140w - SEAGATE ] to my HP-UX D clas machine which is having GSC add-on fast/Wide scsi- interface, but the disk is not shown when i do ioscan, Also of late I find that If I boot the system with that external disk connected , syetms is unable to find the inetrnal boot disk and it throws msg console which keeps on scrolling - retry hot swap disk .

Is it like that you cannot connect any other make disk with HP UX box...

Thanks in Advance

Re: EXTERNAL SCSI- DISK FOR HPUX

Insu Kim — Mon, 24 Sep 2001 11:12:54 GMT

This is my guess.
You try to add an external disk drive to the existing scsi interface at the back.

In this case, you should be aware that it's also been used for connecting internal disk drives, which means that you have to be cautious not to cause any scsi conflict between internal disk drives and the disk that you try to add to the system.

There is one more thing that you keep in mind , that is terminator packs - usually, they're yellow.

On the scsi interface, there're two holders for terminator packs.
For a scsi interface that is being used for internal disk drives, if they're in holder A, they should be moved to holder B in order to support both internal disk drives and external disk drives.
This rule also applies to any scsi interfaces installed for only external disk drives.

Hope this helps,

Re: EXTERNAL SCSI- DISK FOR HPUX

Sanjay_6 — Mon, 24 Sep 2001 12:02:10 GMT

Hi Ajay,

There could be a scsi id clash. try to change the scsi id of the external disk and see if it helps. Also are you using a terminator when you connecting an external disk.

Hope this helps.

thanks

Re: EXTERNAL SCSI- DISK FOR HPUX

paul courry — Mon, 24 Sep 2001 15:56:52 GMT

Uhoh! Did you say ST39140W? Not WD?

If it's a W and NOT a WD I hate to tell you, but you are up the creek without a paddle. Ioscan chops off the last character when display make and model. HP D class machines only work with WD type drives.

Look at the drive itself, the make and model are on it, don't rely on Ioscan.

Re: EXTERNAL SCSI- DISK FOR HPUX

Michael Lampi — Mon, 24 Sep 2001 16:17:46 GMT

The problem is almost certainly due to you
connecting a single ended SCSI disk drive to
your fast-wide-different host SCSI bus. HP did
everyone a disservice by not labeling their
wide host buses as "differential" when they
knew that there were (then) two different types
of wide SCSI buses available. Now there are
three different types of SCSI buses (single
ended (SE), high voltage differential (HVD) and
low voltage differential (LVD).

Only LVD and SE devices can be used on the
same bus (with restrictions). You must not mix
HVD devices with SE or LVD devices.

The only other reason you would have such
problems is if you chose the same SCSI ID's for
the external disk drive as you have for the
internal disk drive, or for the internal SCSI
host initiator ID. The initiator ID is usually
at ID 7, and the boot disk is usually ID 6.
So, pick any unused ID in the range 0-15 and
you should be fine.