| Fred,
a single HSZ40 can have up to four host ID's in the range from 0-7.
In a nonredundant configuration an HSZ40 will always show up to the host with
all ID's configured (preferred ID's are ignored here).
In a dual redundant configuration, you can balance the load by setting
preferred ID's.
As always, you have to follow SCSI configuration rules, where you may not have
more than one identical ID on a single SCSI (SE or diff.) bus.
The target ID on the HSZ is not configurable by software. This is the controller
ID of the single ended buses, where all the disks are connected to.
This ID is either 6 or 7, depending on the position in the controller shelf the
HSZ is mounted.
Hope this helps,
�tzi
|
| Hello !
Also some confuse to me. For the configuration as below
A2100/KZPSA------------------HSZ40=HSZ40-------------------A2100/KZPSA
Host bus id"a" host scsi id "b,c" Host bus id"d"
Prefer id (a,b,c,d)
Isn't that you mean "b,c" could be range from 0-7. and must different
with "a" and "d". Right or not ? Are they share the same scsi bus?
And the prefer id (a,b,c,d) are different bus id with "a,b,c,d",that
are use for controller of HSZ40 load balance.That mean disk
D002,D100,D110,D150 will be accessed from controller prefer id with
(0,1). And D200,D210,D300,D310,D340 will be accessed from Prefer id
(2,3).
Thanks,
Fred.
|
| Hello Fred,
the HSZ has two sorts of ID's. One is the FWD (fast-wide-diff.) ID, which
is presented to the host.
> A2100/KZPSA------------------HSZ40=HSZ40-------------------A2100/KZPSA
> Host bus id"a" host scsi id "b,c" Host bus id"d"
Prefer id (a,b,c,d)
No, the ID=(a,b,c,d) represent the HOST ID's BOTH controllers can have.
The ID's they really have is determined by the PREFERRED_ID.
The amount of preferred ID's on one HSZ has to be less or equal the configured
ID's. In a nonredundant configuration the preferred ID's are the same as the
configured host SCSI ID's. If you define preferred ID's in a dual redundant
configuration on one controller, the other will take the remaining as preferred.
So our picture looks like this:
A2100/KZPSA--------HSZ40===========HSZ40-------------------A2100/KZPSA
Host bus id"e" ID "a,b,c,d" ID "a,b,c,d" Host bus id"f"
Pref id (a,b) Pref id (c,d)
> Isn't that you mean "b,c" could be range from 0-7. and must different
> with "a" and "d". Right or not ? Are they share the same scsi bus?
You MAY NOT have 2 or more identical ID's on one SCSI bus. EVERY node on the
bus MUST HAVE A UNIQUE ID.
> And the prefer id (a,b,c,d) are different bus id with "a,b,c,d",that
> are use for controller of HSZ40 load balance.That mean disk
> D002,D100,D110,D150 will be accessed from controller prefer id with
> (0,1). And D200,D210,D300,D310,D340 will be accessed from Prefer id
> (2,3).
Preferred ID's are not configurable on the "single ended side" of the HSZ.
There are just SCSI buses (called "ports" in the documentation), and we build
higher level, host visible units with the devices ("targets") sitting there.
The HSZ takes the unit number and makes it available to the hosts via the
differential bus in the way you described above.
Take a look at the HS Family Controllers Users Guide. It's all documented there.
Martin
|
| Hello Fred,
the HSZ and the HSD and the HSJ are equal in the way they treat their units.
The HSZ is different in the way it makes the units available to the host.
The difference is, HSD and HSJ controllers create MSCP units, and the HSZ
creates SCSI units.
MSCP units are just numbered 0,1,....16383 (I think), with a free numbering
scheme.
With SCSI, to get more than 7 (without controller) units onto one SCSI bus,
sub-addresses were introduced to get around this limitation.
�tzi
|