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3750 - SDM - Port Statistics

rwamstutz
Level 1
Level 1

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.

4 Replies 4

wdrootz
Level 4
Level 4

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.

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.

Collisions are normal on half duplex Ethernet.

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

Luxembourg

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