🚀 go-pugleaf

In article <BxB1tq.FFw@micrognosis.co.uk>, nreadwin@micrognosis.co.uk (Neil Readwin) writes:
|
| Can you run DECnet over multiple Ethernet adapters? If so, under what
| conditions? Would it work with:
| 
| 	1) 2 adapters on the same piece of wire with every node in the
| 	   same area?

No.  A DECnet Phase IV node can't have two interfaces on the same Ethernet,
because DECnet embeds the node's network-layer address in the interface's 
Ethernet "physical" address so that it doesn't have to use ARP or something
like it.  So you would wind up with two interfaces on the same Ethernet
with the same Ethernet address which won't work.

| 	2) 2 adapters on 2 networks with every node in the same area?

Sure, this would be the usual way to do it.

| 	3) 2 adapters on 2 networks with a different area for each node?

This would work too (assuming that you made each node an area [level 2]
router), but it would be perverse.

| If anyone can point to a section of the Networking Manual that I have missed
| then please do so :-) Neil.

I'm afraid I don't know whether I've seen this stuff in any manual.

Might I ask why you would want to do this?  Your ordinary DECnet guys
just buy bridges if they want to partition their network.  (And a bridge
will pass traffic better than any VAX will, and reboot faster.)

Best,

Aaron

Aaron Leonard (AL104), <Leonard@Arizona.EDU>
University of Arizona Network Operations, Tucson AZ 85721
  "It's not a bug, it's a form of flow control."
  - Jerry Leichter on why crash-prone Unix is a suitable
    platform for NSFNET core routers

In article <1992Nov6.192244.3956@arizona.edu>, leonard@telcom.arizona.edu (Aaron Leonard) writes:
|> [I wrote:]
|> | Can you run DECnet over multiple Ethernet adapters? If so, under what
|> | conditions? Would it work with:
|> [...]
|> | 	2) 2 adapters on 2 networks with every node in the same area?
|> 
|> Sure, this would be the usual way to do it.
|> 
|> | 	3) 2 adapters on 2 networks with a different area for each node?

Whoops, I meant a different area for each network.

|> Might I ask why you would want to do this?

The question came up in a discussion of whether we should stop bridging 2
of our networks and route between them instead.  Someone said (incorrectly,
as it turns out) "You can't run DECnet over 2 Ethernet adapters". We can
probably solve our problem by configuring the bridges to prevent certain
protocols passing through them, but we wanted to know if routing was
possible. Cheers, Neil.
-- 
 Phone: +44 71 815 5283  E-mail: nreadwin@micrognosis.co.uk
 Anything is a cause for sorrow that my mind or body has made

In article <BxD4vs.1By@micrognosis.co.uk>, nreadwin@micrognosis.co.uk (Neil Readwin) writes:
| |> [I wrote:]
| |> | Can you run DECnet over multiple Ethernet adapters? If so, under what
| |> | conditions? Would it work with:
| |> [...]
| |> | 	2) 2 adapters on 2 networks with every node in the same area?
| |> 
| |> Sure, this would be the usual way to do it.
| |> 
| |> | 	3) 2 adapters on 2 networks with a different area for each node?
| 
| Whoops, I meant a different area for each network.
| 
| |> Might I ask why you would want to do this?
| 
| The question came up in a discussion of whether we should stop bridging 2
| of our networks and route between them instead.  Someone said (incorrectly,
| as it turns out) "You can't run DECnet over 2 Ethernet adapters". We can
| probably solve our problem by configuring the bridges to prevent certain
| protocols passing through them, but we wanted to know if routing was
| possible. Cheers, Neil.

One recommendation, if you do decide to go the routing route instead of
bridging:

DECnet routing will optimally handle an arbitrary topology if all nodes
are in a single area.  But if nodes are in separate areas, traffic will
take suboptimal routes because interarea traffic must pass thru
level 2 routers even if such a path is physically unnecessary.

So I would DISRECOMMEND assigning separate areas to each DECnet 
"subnet", but instead give everyone addresses within a single area,
up until you reach your 1K node limit.

Aaron