Hello to everyone,
First, thanks again for all the helpful people who replied. You are too
numerous for me to list (BTW, is there an easy way with eudora to print a
list of all the people who replied whitout having to cut and paste like
crazy ?)
Here are my two questions and a summary of the answers I received:
*********************************************************
* 1st question *
*********************************************************
Dear managers,
I presently have a TZ87 and a TZ88 installed in 2 BA36R-AF shelves behind 2
dual-redundant HSZ40's. These 2 drives are taking valuable space in the
shelves and I would like to move them out of the HSZ40 configuration and
replace them with 6 4Gig drives.
I'm planning to do the follwoing and wanted to make sure that:
a) this is feasible
b) I've got the correct part numbers
I will order a BA36R-AF shelf with extra PW supply that I will mount in my
server rack. I know that you can split a BA36R-AF shelf in two, creating
two scsi buses, but I was wondering if these 2 buses can be used by two
different hosts.
>ANSWER: Yes, this is feasible. The bus will be split in two, one bus will
>have 3 SCSI IDs and the other will get 4. In my case, I will add a second
>power supply to the shelf, so I'll have two buses containing 3 IDs. You
can >look at the BA356 manual to see how the IDs are distributd.
I will also order 2 PCI SCSI controller cards and 2 cables for my 2 alpha
servers 2100. Here is what I plan to do:
---------- HOST A (KZPAA) SCSI BUS 2
|
BA36R-AF: |
---------------- JA1 |
|P|P|TZ-|TZ-|x-|--------|
|W|W|87 |88 | | JB1
|R|R| | |x-|------------------ HOST B (KZPAA) SCSI BUS 2
---------------- Cable (Part #?)
^
/|\
|
i/o module
What is the max lenght of the cable between the I/O module and the KZPAA
and what is the part # that I should order ?
>ANSWER: The BA356 itself uses approx 1m of SCSI cable. I am planning to
use >KZPAA-AA adapters (fast SCSI narrow adapters) and the max lenght is 3m
with >this standard. So I'll have to buy the following cables:
>BN-21H-02
>These cables are 2m long and each end is "straight". I have to use
straight >ends because I will add a 8 bit personality module in the BA256
shelf. If you >keep the 16 bits module, you need the 1 right angled variety
of cable.
Provided that I set the BA36R-AF jumpers to "split" it, and that I set the
ID jumpers on the TZ87 and TZ88, can I come out with a solution like this:
HOST A sees the TZ88 as SCSI-ID 2 on bus 2, HOST B sees the TZ87 as SCSI-ID
5 on bus 2
>ANSWER: Yes. Something like this. You have to see the BA356 manual to see
how >the IDs are attributed to the different buses. I will probably have to
set >the device IDs directly with the dip switches behind the TZ-xx.
The BA356 documentation is talking about TERMINATOR BOARDS (BA35X-MB) and
BA35X-MC JUMPERS ? Do I have to order these things separatly or do they
come with the shelf ?
>ANSWER: Normally, the BA35X-MB comes with the BA356 that you ordered. But
my >field engineer told me that this item is missing most of the time, so
you >better order one specifically. The BA35X-MC jumper is included with
the BA. This part number is to be used only if you lose it and need a
spare.
Addendum:
I just discovered that my machine is a DEC ALPHA 2100RM, not a 2100A, so I
only have 3 PCI slots and all of them are currently used, the first by a
KZPSAonnecting to our HSZ, the second and the third by 2 network cards (One
100Mb and another spare card at 10Mb in case of failure of the primary NIC)
>ANSWER:
>
> I still got one PCI slot left after all. I noticed that the 10mb ethernet
> > card is built-in the server.
I searched the DEC catalog hoping to find an EISA equivalent of the KZPAA
(Dumb FASt SCSI card) but could not find anything. Of course, I could
remove the 10mb ether card and replace it with a KZPAA, but again, my
future expansion needs would be ruined.
>Dec used to sell an EISA 8 bit fast SCSI card, but it is not in the
catalog >anymore. The following card also work (I think it's an adaptec
board)
>
> The only EISA SCSI adapter that is supported is the
> AHA-1740/1742. This is probably a Slow/Narrow/Single-ended
> adapter, but there is a driver for it.
>Anyway, EISA is phasing out (thanks God) and it's a waste of money,
>considering the kind of performance you would get.
>See my summary (it will come soon) about the 2100 -> 2100A upgrade.
>Meanwhile, we decided to fill the PCI slot with a KZPAA. When we'll do the
>2100->2100A upgrade, We'll have plenty of PCI slots avilable.
*****************************************************************
* 2nd question What to do when you have multiple HSZ
*****************************************************************
Hello,
We are presently using DecSafe in a DU 3.2D-1 environment. We have 2
HSZ40's configured in dual redundant mode.
Our HSZ40's are quite loaded and we are wondering what to do when all the
storage shelves will be filled. Does DecSafe support more that ONE shared
SCSI bus ?
For example:
Actual Config:
HOST1 HOST2
| | pci bus
KZPSA--------- HSZ40 (2)----------- KZPSA
|
SHARED STORAGE
Can we just add a second KZPSA in each server like this to increase storage
performance without swamping the KZPSA with I/O's:
HOST1 HOST2
| |
KZPSA--------- HSZ40 (2)----------- KZPSA
| | |
| SHARED STORAGE | pci bus
| |
KZPSA--------- HSZ40 (2)----------- KZPSA
|
SHARED STORAGE
Or is it possible to have more than 1 set of HSZ40 connected to our actual
KZPSA even if it causes heavy I/O ?
HOST1 HOST2
| |
KZPSA--------- HSZ40 (2)----------- KZPSA
| | |
| SHARED STORAGE | pci bus
| |
------------ HSZ40 (2)---------------
|
SHARED STORAGE
In those case, how does the SCSI ID work ? For now, one of the HSZ40 is
configured as SCSI 6, the Other hase 7. The prefered ID's of the first
HSZ40 is 1,2 and the second one are 3,4
Are the prefered ID's reserved ID's from the KZPSA SCSI BUS or
is it "virtual" ?
ANSWER:
DecSafe supports multiple shared SCSI buses. You can add additionnal
KZPSA's or add other HSZ40's to your actual SCSI bus. The later is not
recommended because it will overload the BUS. Remember that you only have 7
SCSI IDs that you can use. If you load the bus too much, you risk the bus
reset.
The best is to put only one pair of HSZ40 per KZPSA scsi bus (if you use
dual redundant HSZ40) or 2 HSZ40 in non redundant config per SCSI bus.
As for the "virtual" IDs, there is no such thing. If for example you have a
KZPSA with ID 6 at one end, two HSZ40 (the first servicing targets 1,2 end
the second 3,4) and another KZPSA with ID 7 at the other end, all you have
left is SCSI ID 5 (this could be another HSZ40)
I forgot to take a look at the DecSafe Hardware manual, it's all explained
in great details, but not very easy to understand for a SCSI neophyte.
Thanks again !
Received on Fri Apr 11 1997 - 00:57:45 NZST