Conference netcad::hub_mgnt

3457.0. "decbridge 90 stops forwarding" by MUCCS1::GRAF () Tue Apr 16 1996 11:22

Hi,

We have a strange problem with several DECbridges 90 (DEWGF).

Here is a short description of the network topology:

The customer has a central DEChub 900 which contains a DECrepeater 900FP.
From that repeater there are 7 fiber connections to DECbridges 90 which 
are seated in DEChub 90s.

Yesterday evening all of the 7 DECbridge 90s suddenly stopped forwarding. 
When that happend the Forwarding State LED came on and stayed in that 
non forwarding mode even after powering down and up again. The customer 
plugged in a spare DECbridge 90 which was working fine. But all other 
bridges stayed in the "non forwarding state" even after several power ups.
Because of these problems the whole production line stood still for the 
whole night. Curiously enough, the bridges went in normal oparation mode 
by themselves in the next morning and are operating just fine now. 
There is no hint of what was causing that failure. 

What event can cause all the  DECbridge 90s going into the non forwarding 
state and stay there for houres? The customer is very worried, because when 
that will happen again there will be another big loss of production. 

The bridges were installed 2 years ago and there were only minor problems 
since then. 

Revisions:   FPROM V3.0 
	     DEWGF V2.1 


.. any hints are appriciated. 


regards, Helmut