Late collision -890 ISR

[amh4y0001]

Hi,

I have Cisco 890 series ISR and I am getting random errors like this:

%PQ3_TSEC-5-LATECOLL: Gi8, Late collision

What I have checked so far is:

1. Checked the cables and even replaced the cables (Cat5e and Cat6).
2. Updated the IOS from c800-universalk9-mz.SPA.154-3.M3 to c800-universalk9-mz.SPA.154-3.M9.
3. Replaced the Router with a fresh installation of the c800-universalk9-mz.SPA.154-3.M9.
4. Problem persists even after OS update and changing of the Router itself.

I have same setup on multiple locations, and only one location started to produce this error. Do someone has information how to isolate and troubleshoot the problem?

[Georg Pauwen]

Hello,

what is connected to Gi8 ? Since you have done a hard and software replacement on all possible components, it is likely that the device connected to Gi8 is the culprit...

[Richard Burts]

I agree with Georg that the issue may well be with the connected device. The symptoms suggest that it might be mismatched duplex. If your router is operating in half duplex you will check for collisions. If the connected device is operating as full duplex it does not check for collisions and may very well begin transmitting as it is receiving something from you. That could very easily result in your detection of a late collision. Check the duplex operation of both devices and let us know what you find.

HTH

Rick

[Leo Laohoo]

Post the complete output to the command "sh interface g8".

[Joseph W. Doherty]

In addition to what the others have posted, if you have a full duplex network (and unless something is misconfigured, half duplex, today, is often rather rare), you shouldn't be seeing anything about collisions.

In a correctly operating half duplex network, collisions are normal, late collisions indicate something not operating to spec.

Rick's reply describes a common cause, i.e. misconfigured NICs.

[amh4y0001]

Hi,

On Gi8, I have WAN link (DHP Enabled). Here I may have ,imitation as I can't check the operating duplex if its half or full. 

[Leo Laohoo]

Just post the command "sh interface Gi8".