intermittent flashing amber light on 3550 switch

[silks101]

We hav a switch on site that is functioning normally - all interfaces are working fine, but on regular occassions a couple of ports start flashing amber for a few seconds before going back to the normal flashing green lights.

Does anyone have any idea what this means?

 

[Andyleates]

Have a look at the ports interface statistics. I expect you will see some collisions or CRC errors...

Post what you see here for more help.

Andy Leates MCSE CCNA MCP+I

 

[silks101]

This was the output from one of the interfaces - it does show a few CRC errors: Any thoughts

MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 251/255, txload 2/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 100Mb/s, 100BaseTX/FX
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:48, output 00:00:00, output hang never
Last clearing of "show interface" counters 00:03:08
Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
5 minute input rate 739000 bits/sec, 190 packets/sec
5 minute output rate 816000 bits/sec, 284 packets/sec
35768 packets input, 17296253 bytes
Received 17190 broadcasts, 0 runts, 0 giants, 0 throttles
1130 input errors, 567 CRC, 563 frame, 0 overrun, 0 ignored
0 watchdog, 17190 multicast
0 input packets with dribble condition detected
54035 packets output, 18898869 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier

 

[rburke]

Have you made sure the speed and duplex settings are correct on both devices? (ex 100/full, 10/half, etc). Also, if the duplex settings are correct, then I would try replacing the cable. Although a long shot, cables DO go bad sometimes(although rarely).

Burke

 

[baddos]

Yeah... It looks like the port is hard set to 100-Full Duplex. If you hard set the ports, you need to hard set the host's NIC card to the same as the switch.