Collision errors with hub attached to 3750.

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Aug 21st, 2009
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Hi,


I'm getting collisions on a port on my 3750 where a 3com 10/100mb hib is attached. Due to hubs working in half duplex I decided to set the interface to "duplex half" and "speed auto" and the port goes down (no green or amber lights). If I set the interface to "duplex half" "speed 100" I get the same response, as soon as I do a "no duplex" and "no speed" the interface comes back up with and works but with collisons.


i thought setting to half duplex will remove the collisions not the function of the port :/ ?

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Jon Marshall Fri, 08/21/2009 - 04:55
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"i thought setting to half duplex will remove the collisions not the function of the port :/ ?"


No it wont. If the link is running at half duplex then you will always see collisions. That is the whole idea of using a switch and running full duplex on the links ie. no collisions.


Is there a reason you are connecting hubs to your switches ?


Jon

whiteford Fri, 08/21/2009 - 05:00
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The single port goes into a test domain running tonens of packet ininstecting tools and sniffers. I span various ports from my stack to this port and the servers on the test domain get the info to analyse.


So a hub on a switch will always see collisions, no probs.

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