1841 Collisions Error

Answered Question
Feb 26th, 2008

I've been getting disconnected from My collo, and wondering if this error is the problem, "*Feb 26 17:00:16.083: %GT96K_FE-5-LATECOLL: Late Collision on int FastEthernet0/0" I know a collision can't be that bad, but can too many of them bring down my internet connection?

Right now I have my config in auto duplexing, If I forced it to do a full duplex there will be additional downtime, I want to make sure before I apply this setting that the collisions are the problems, or if the NIC card on the 1841 are bad, because this is my second one.

Thanks in advance for your reply.

I have this problem too.
0 votes
Correct Answer by Richard Burts about 8 years 9 months ago

Josue

There is a difference between a collision and a late collision. A collision is normal if you are operating in half duplex mode. A late collision is not normal. Especially if there are very many late collisions it is probably a sign of a duplex mismatch. If you are half duplex and the other device is full duplex it will create late collsions on your device (and may also create runts which you might see in the output of show interface).

Before you make changes I would suggest that you check with whoever manages the device that you connect to. It sounds to me like you are attempting to negotiate (proably both speed and duplex) and that they are not negotiating - or at least not negotiating duplex. It is best if both devices are configured the same. Either both should negotiate or both should specify speed and duplex. (and setting speed prevents negotiation of duplex).

The good news is that if you decide that the solution is to configure your 1841 to specify full duplex is that it will adapt and be back in operation in only a couple of seconds.

HTH

Rick

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 5 (1 ratings)
Loading.
Correct Answer
Richard Burts Tue, 02/26/2008 - 10:17

Josue

There is a difference between a collision and a late collision. A collision is normal if you are operating in half duplex mode. A late collision is not normal. Especially if there are very many late collisions it is probably a sign of a duplex mismatch. If you are half duplex and the other device is full duplex it will create late collsions on your device (and may also create runts which you might see in the output of show interface).

Before you make changes I would suggest that you check with whoever manages the device that you connect to. It sounds to me like you are attempting to negotiate (proably both speed and duplex) and that they are not negotiating - or at least not negotiating duplex. It is best if both devices are configured the same. Either both should negotiate or both should specify speed and duplex. (and setting speed prevents negotiation of duplex).

The good news is that if you decide that the solution is to configure your 1841 to specify full duplex is that it will adapt and be back in operation in only a couple of seconds.

HTH

Rick

jlouis1920 Tue, 02/26/2008 - 10:21

Thanks A lot Rick I will check with my neigbhor configuration before I apply this setting. Thanks Once again

Actions

This Discussion