long@nic.near.net (Daniel Long) (09/18/90)
We're having a problem with the interaction between a Cisco Gateway (MCI
Ethernet interface) and a Cabletron MMAC-8. Specifically:
We have a LAN composed of a Cabletron MMAC-8 "Cardcage" or "Hub". This hub
comprises 1 bridging module, and several interface boards for each of: twisted
pair, thinwire, thickwire, and fiber. In addition, one of the thickwire ports
is connected to a Cabletron ND25E Bridge which, in turn, is connected through a
transceiver to a stretch of thick Ethernet cable.
Our Cisco gateway was connected through a transceiver to one of the thinwire
ports. It was working fine for weeks and then suddenly started reporting lots
of frame errors. This has continued almost steadily (there were a few minutes
this morning when this problem did not manifest itself).
The rest of the hosts on the LAN are not seeing any errors nor does a Sniffer
plugged into the same port see any problems. We've swapped ports, media (thin
vs. thick vs. twisted), transceivers, and cables and nothing makes any
difference.
When you put the cisco's Ethernet interface into loopback or when you create a
separate stub Ethernet connecting it to another cisco, the interface works
fine. Also, when you connect the cisco to a transceiver on the thick Ethernet
cable (behind the bridge) it can talk to the hosts on that segment (and
presumably to the rest of the LAN).
So this seems to be one of those nasty cases where each side works
independently but the two don't work together. Any suggestions/wisdom?
Thanks,
Dan
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Ethernet 0 is up, line protocol is up
Hardware type is MCI Ethernet, hardware address is 0000.0C00.080B
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec, rely 160/255, load 1/255
Encapsulation is ARPA, loopback is not set, keepalive is set (10 sec.)
ARP type: ARPA, HP-PROBE
Last input 0:00:01, output 0:00:00, output hang never
Output queue 0/100, 0 drops; input queue 0/75, 0 drops
Five minute input rate 1072 bits/sec, 2 packets/sec
Five minute output rate 1006 bits/sec, 1 packets/sec
1702 packets input, 116169 bytes, 0 no buffer
Received 1187 broadcasts, 34 runts, 0 giants
35286 input errors, 33 CRC, 35268 frame, 0 overrun, 32 ignored, 0 abort
617 packets output, 75414 bytes
0 output errors, 1 collisions, 0 interface resets, 0 restarts
GS Software, Version 8.0(13)
MCI 1, controller type 1.0, microcode version 1.4
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