Re: Spooky Routing by Sun TCP/IP


Doug Nelson (08071DEN%MSU.BITNET@CUNYVM.CUNY.EDU)
Tue, 19 Jan 88 17:32:04 EST


>We have a bunch of Suns configured on several seperate nets something like:
> +-----------------+
> | VM running KNET |
> +-----------------+
> |
>-----------+----------+----------+--------------- 193.9.200 Ethernet
> | |
> +---+---+ +---+---+
> | Sun A | | Sun B |
> +---+---+ +---+---+
> | |
> -----------+----------+--------- 193.9.202 Ethernet
>
>We have a problem where VM tries to talk to Sun B using Sun A as a router,
>but Sun B responds to VM using its 193.9.200 interface. Since VM does not
>have the 193.9.200 interface for Sun B defined, it ignores the response.
>
>Questions: Is the Sun trying to be smart, recognizing it can get to the
>193.9.200 net in one less hop by using a different interface to respond on?
>If so, is there a way to turn off this smartness without unplugging the
>second interface?

Is the Sun responding to the KNET using its 193.9.202 address (it should
be)? If so, it shouldn't matter that the response comes back on the
"wrong" interface. What version of the KNET software are you running?
I have seen cases where it refuses to acknowledge other nodes that aren't
listed in its tables, and I suspect this is another symptom of that problem.
I also think that this may be fixed in the latest KNET release.

So, the answer may not be that the Sun is being too smart, but that the KNET
is being too dumb.

Doug Nelson
Michigan State University
Computer Laboratory



This archive was generated by hypermail 2.0b3 on Thu Mar 09 2000 - 14:40:41 GMT