I am getting some complaints from users on a telnet app that is breaking. It seems like the session freezes. They get an error. I researched the error and I found that it was a connectivity problem.
So I looked at the interfaces of the switch where these people site. here is an an example:
FastEthernet2/12 is up, line protocol is up (connected)
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
418 packets output, 47790 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
Most of the time this is how they look. All the ports look good.
Ocassionnally I see an increment on 1 lost carrier. This happens to all ports on the switch. And then it goes away. I have not been able to correlate the lost carrier increment and the lost telnet session. What does it mean to have a lost carrier? I guess my question is could a lost carrier break a tcp session?