SUMMARY: SCSI peripherals upgrade on DEC 3000/500

From: Joerg Bruehe <joerg_at_sql.de>
Date: Mon, 14 Feb 2000 15:52:12 +0100

Dear admin colleagues !

For my question, I got answers from
    Joe Fletcher <joe_at_meng.ucl.ac.uk>
    Dr. Tom Blinn <tpb_at_doctor.zk3.dec.com>
which I insert below (unquoted) at the respective questions.

In addition,
    Alan Davis <Davis_at_tessco.com>
sent me these URLs
    http://www.digital.com/alphaserver/archive/2100/2100_tech.html
    http://www.digital.com/alphaserver/archive/axp/dec3000.pdf
(unluckily, this last one does not cover my DEC3000_500 - see below,
and thanks nonetheless, it was worth a try), and
    Udo de Boer <udo.de.boer_at_live.demon.nl>
warned me that an upgrade to DU5.0 might, at least when using LSM,
scribble on all disks.

My sincere thanks to all of them !


See here for the (shortened) questions and the answers:

Joerg Bruehe (= I myself) schrieb:
> We operate a DEC 3000_500 and a 2100_C500 MP, ((...))

Dr. Tom Blinn warned me the 3000/500 is an old system and should
be scrapped.
I agree, but as long as it works and the costs of keeping it up
are low, I will postpone the exchange for about a year or two.
However, even Compaq web sites seem to have no docs for it ...


> ((...))
>
> My purpose is to increase disk capacity on the 3000/500
> and tape backup capacity on either of the two.((...))
>
> a) I assume the SCSI devices to be single-ended, narrow.

Joe Fletcher and Dr. Tom Blinn agree these are narrow, single-ended.

 
> b) ((...))
> In the external cabinet "BA35X-VA", can I replace two RZ28
> by one or two larger disk(s) ((...)) ?

Both Joe Fletcher and Dr. Tom Blinn agree this is possible in
principle, but warn me about potential heat problems.
I will have to look for any additional info on that cabinet,
the Compaq web site does not carry anything about a "BA35X-VA"
(which is what I found on the label).
Seagate does DEC specific variants (carried by Transtec),
and a newer enclosure with increased cooling is also an option.

Note: Transtec (for me: Germany) offers a Seagate ST34520N
(4.55 GB) and a ST39140N (9.1 GB), both rated at 11 W.
However, I found no information telling me the Digital RZ28's
power consumption or the BA35 cabinet's specification ...
I guess I will take the risk to replace 3 RZ28s (3* 2 GB)
by one 9 GB Saegate, leaving the immediately adjacent slots empty.


>
> c) ((...)) Is a TZ87 the same as a DLT III drive, or does it just
> look similar ?

It is a DLTIII.

>
> d) ((...))
> If I take out one device (any restrictions ?),
> could I then insert the TZ87 in the SCSI bus between system
> and expansion cabinet ?

This is possible if duplicate SCSI ids are avoided and the cables
are not too long.

>
> e) Would it be easier to connect an external tape to the 2100 ?
> ((...))

Quote Dr. Blinn:
The 2100 is a somewhat more modern system, but it was the very first of
the PCI based server systems. The "psiop" driver usually is operating
an NCR 53C810 based SCSI fast narrow single ended adapter card. These
cards usually have both an internal and an external ("MD50") interface
and there is a jumper on the card that determines whether it terminates
the bus. If the jumper is installed, then the card terminates the bus
and you can only connect a cable to one of the two interfaces. With the
jumper removed, you can connect both internal and external cables, but
you still have to be careful about the total end-to-end lengths since
that adapter is not easily programmed to run slow instead of fast.
   --- end of quote ---

>
> f) Is there any other backup device you would recommend,
> especially one that fits internally (= 3.5 " size) ?

Joe Fletcher: "Stick with DLT. Better, stronger, faster than DAT."


Again, thanks for the answers,
and much success to all of you !

Regards,
Joerg Bruehe

-- 
Joerg Bruehe, SQL Datenbanksysteme GmbH, Berlin, Germany
     (speaking only for himself)
mailto: joerg_at_sql.de
Received on Mon Feb 14 2000 - 14:51:50 NZDT

This archive was generated by hypermail 2.4.0 : Wed Nov 08 2023 - 11:53:40 NZDT