Link level Ethernet bridges problem solved


C. Philip Wood (cpw%sneezy@LANL.GOV)
Thu, 25 Feb 88 16:39:36 MST


I want to thank all of you who responded with many helpful suggestions.
And as usual, it appears that the original understanding of the problem
did not lead me to any reasonable conclusion. The bridge was not a factor.

In particular thanks to 'Merle'

> I dont know if this is your problem but you might look
> at the local ether segment to see if some transcievers
> have been installed improperly etc.

and Doug Blair

> I had an installation with an HP 9000 that had the same problem.
> The HP people swore up and down that their transceiver was fine, but I
> swapped it out anyway and guess what? it worked. I would assume that
> other folks might have this problem with their transceivers, and am
> not throwing stones at HP in particular.

We sent some folks in the know out to investigate the segment with the HP
on it. It turns out that the DEC lanBridge and all the hosts on the
second segment had nothing to do with the problem. What follows is a
more detailed picture of the problem and the "fix".

        Ha Hp Miscellaneous hosts DEREP****LanBridge
        | ? | (Apollo,Sun,IBMPC) |
        | | | |
        C.......+.+...................................DESTA
                1 2
Ha== Sun UNIX 4.2 Release 3.4
Hp== HP-UX hp320 6.01 B 9000/320
+ == Thinnet transceiver? with BNC connectors
. == Thinnet
C == BNC connector
* == Fiber
? == no connection

No one seems to know what the extra + was doing connected via 1 foot of
Thinnet at location 1. However, 1 was swapped with 2 and things started
to work. It was decided to initial #2 with "NG" and remove it from the
configuration as follows:

        | |
        C.........+...................................DESTA

Phil Wood, cpw@lanl.gov



This archive was generated by hypermail 2.0b3 on Thu Mar 09 2000 - 14:41:30 GMT