| re: <<< Note 345.0 by ATZIS4::HAINZL_R >>>
>1 FDDIcontroller 400 and
>1 DECbridge 6xx (3 Ethernets)
>to a DECconcentrator.
Richard,
A couple of things. First, I think the FDDIcontroller 400 is a SAS device,
and therefore requires connection to a DECconcentrator M port (not A or B).
The DECbridge can be DAS or SAS, as you have indicated.
The simplest configuration would be an "FDDI in a box" solution, consisting
of a DECconcentrator 500, with a DEFCN-MA management board, and a DEFCN-NA
(4 port SAS board).
I don't know if its possible to run without the management board, and I
wouldn't recommend it anyway.
Hope this helps...
Bob
|
| The configuration in the base note is definitely NOT a good idea, but it
IS permitted. (S ports can connect to anything, even A and B.) The reason
it's a bad idea is that A and B ports are meant to form a dual ring, so
A should connect to B. If you connect A or B to S, that creates a wrapped
ring, just as if you had a dual ring with one failure. In a wrapped ring,
any additional failure will partition the network.
There's an even cheaper configuration which is often forgotten: you can connect
an S port directly to another S. This results in a two-node FDDI. Any
extension of this configuration requires a concentrator, of course. But if
you have a special bounded requirement of exactly two nodes, or you want
to connect two nodes quickly for test purposes, just connect them directly.
So your minimum configuration is just a DEFZA and a DECbridge-610, with the
cable to connect them...
paul
|