[comp.dcom.lans] Ethernet/Optical link locking upREAD/NEW

oberman@amazon.llnl.gov (07/09/90)

In article <1864@trlluna.trl.oz>, gotch@rhea.trl.oz.au (Rob Gotch) writes:
> Our problem is that, occasionally, one of the repeated links locks up.
> Close inspection of the equipment reveals that the ANC-20 MAU's at each
> end of the affected link show the collision detect light hard on.
 
I suspect your analysis is pretty accurate. The problem is most likely the
ANC-20s. Sort of.

The problem is that you are using DEREPs. These are devices that predate 802.3
and don't comply with the spec for repeaters. They are pretty much Ethernet V2
complient. So they need a real V2 MAU. DEC specifies that the H-4000 be used.
Even their own 802.3 MAU, the H-4005, is not acceptable.

Replace the ANC-20s with H-4000s (Yuch!) and I suspect your problem will go
away.

					R. Kevin Oberman
					Lawrence Livermore National Laboratory
					Internet: oberman@icdc.llnl.gov
   					(415) 422-6955

Disclaimer: Don't take this too seriously. I just like to improve my typing
and probably don't really know anything useful about anything.