Sorry for going off topic but I trust &SMers using AIX can help.

I'm looking to 'buy time' until the new system arrives and want to add
external DASD ... err I mean DISKS to my AIX-RS6K-H50. I'm going to 'give
back' 18 Gig's of SSA to th DB and Staging by using cheap external for
one-drive reclamation disk-FILE area.  which is expendable when empty.

There's a 68-pin scsi connector out the back of the H50.  I've
successfully attached an external SCSI enclosure (50 pin) with a 2 GIG
drive in it using a 50 pin (back to H50) 68-pin cable and then LVM,
format, etc cp -p  to it too!

But as soon as I go out and buy a 18 Gig drive  68 pin it
fails!!!    I have only been able to try LVD (low voltage differential)
drives and they fail.  Luckily I've gotten them from Fry's and can return
them without any hassles.  But that little experiment has been exhausted.
I've even tried so-called converters 50-pin to 68 pin that's suppose to
handle the w/&w/o low voltage conversion for me with no-luck!

In going on EBay I notice some sellers specifiy LVD and Ultra 160 and I
understand I have to avoid those versions.  But there's still confusion on
my part as to whether I can use a Ultra Wide or SE 68 or 80 pin.

A more knowledgable person here told me to avoid any Seagates with L in
the model number because that's LVD and I've learned F means fibre.
But now I'm seeing W and WD and WC but no N's which I'm sure would be OK.

On IBMS , I think I can use DGHS if its an X (as in 18XP) but not if its a
Z as in 18Z.  And I'm avoiding any with  SE/LVD but SCSI is OK in this
line.  The market for non LVD (re: old) scsi is drying up and its tricky!

I would appreciate any other model numbers that definitely are compatible
with a 68-pin external scsi connector that seems to only work with 50pin
drives!!    I have done no research on Western Digital up to now.

             thanks ... joe.f.



Joseph A Faracchio,  Systems Programmer, UC Berkeley
Private mail on any topic should be directed to :
   joef AT socrates.berkeley DOT edu