Quick UDLD Question

Unanswered Question
Sep 3rd, 2010

Can you configure UDLD aggressive on one end and regular UDLD on the other?

Will the switches even accpet it..?

I have this problem too.
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francisco_1 Fri, 09/03/2010 - 07:58

UDLD agressive inteoperates with UDLD normal on the other side of a link.


ex-engineer Fri, 09/03/2010 - 07:59

OK, so the switches will allow this config.

However, in terms of functionality, the link will not truly be a UDLD aggressive link...it will fallback to UDLD....no?

francisco_1 Fri, 09/03/2010 - 08:07

I havent tested it myslef but i believe the link with agressive will stay that way and the other side normal. This type of configuration means that just one side of the link will be errdisabled once “Unidirectional” condition has been detected.


francisco_1 Fri, 09/03/2010 - 08:13

So if one side is agressive and the other side is normal, and the link is determined to be bi-directional and the UDLD information times out while the link on the port is still up, UDLD tries to re-establish the state of the port. If not successful, the port is put into the errdisable state on the aggressive side.

The bahavior of the normal mode, if the link state of the port was determined to be bi-directional and the UDLD information times out, no action is taken by UDLD. The port state for UDLD is marked as undetermined. The port behaves according to its STP state.



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