Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

runt frames on Catalyst 2924


I connected an Alcatel 4400 PBX and a Cisco Catalyst 2924 switch via Fastethernet interface. I checked the counters on this interface and I found a lot of runt frames. I knew that the Ethernet interface of Alcatel PBX is 10Mbps half-duplex therefore I changed the interface of the 2924 to 10Mbps Half-duplex. The result was the same. I changed the cable but it didn't help.

I don't know what is to be done. What can I do? Is there any solution to avoid these runt frames?

Thanks in advance,

Lajos Csemy


Re: runt frames on Catalyst 2924

A runt frame is generally the fragments of a collision. The defintion of a runt is a frame smaller than the media's allowed min frame size which in your case is 64 bytes. This could also mean a faulty port that is just placing junk out on the wire but more likely it is the affect of collisions so hence if possible try and set interfaces to full duplex.

Also do make sure you are within the ethernet physical spec for cable distances etc.


Re: runt frames on Catalyst 2924


Sometimes you need to bounce the port for the duplex setting to take effect. Try this.

CreatePlease login to create content