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New Member

3750 - SDM - Port Statistics

All, on the 3750 SDM, looking at the port statics, what does "Total Transmit Errors" and "Total Receive Errors" mean? Is this collisions, back packets?

Much appreciated.


Re: 3750 - SDM - Port Statistics

Total transmit error it means total number of error packets sent. This includes total runts, collisions, late collisions, and excessive collisions. Total receive error it means total number of error packets received. This includes runts, and FCS and alignment errors.

New Member

Re: 3750 - SDM - Port Statistics

Thank you for your reply. How do I identify what is causing those collisions? I do know the ports I have the most Transmit errors on are running at 10mb/half duplex.

Super Bronze

Re: 3750 - SDM - Port Statistics

Collisions are normal on half duplex Ethernet.

Re: 3750 - SDM - Port Statistics

On some versions of some switches, collisions are included in the error count. For example in the 4500 IOS 12.2(20)EW. This is definitely wrong. Collisions are a normal part of the half-duplex arbitration procedure. In fact, I raised a TAC case about it, and it was fixed in 12.2(25)EWA2.

On the other hand, runts (meaning a packet less than 512 bits long), late collisions (meaning a collision after the 512 bit collision window), and excessive collisions (meaning a packet has been collided more than 15 times) are errors.

Kevin Dorrell