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Ethernet error - LANCE-5-COLL: Unit 0, excessive collisions

I am currently investigating a number of ethernet problems on several networks and have encountered the following message on several:

"%LANCE-5-COLL: Unit 0, excessive collisions. TDR=4

Is it possible that there could be 'excessive collisions' due to simply to traffic volume as opposed to the tranceiver/module/cable problems identified in the earlier response to a similar query?

What Does the "%LANCE-5-COLL: Unit 0, excessive collisions. TDR=4" Error Message Mean?

1 REPLY
Anonymous
N/A

Re: Ethernet error - LANCE-5-COLL: Unit 0, excessive collisions

This error means an Ethernet cable is broken or unterminated, or the transceiver is unplugged.

TDR means Time Delay Reflectometry. TDR is commonly used to refer to an external device that is used to detect a variety of cable problems. TDR is an internal counter that starts whenever a frame is transmitted. The counter increments in ticks of 100 ns(nanoseconds) each. Each tick is equal to approximately 35 feet. The following debug message probably indicates an unterminated network or an excessively long network (over specification).

% Lance-5-coll:Unit 0, excessive collisions. TDR = 39

The AMD Lance (Am 7990) Ethernet Controller manual says that the TDR field "reflects the state of an internal Lance counter that counts from the start of a transmission to the occurrence of a collision. This value is useful in determining the approximate distance to a cable fault."

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