loop Guard /UDLD

Posted on 2016-08-26
Last Modified: 2016-09-02
I need to verify if this is Correct:
 If L2 link (Trunk) exists between 2 switches. Loopguard /UDLP should be configured on every port on both  switches including on the ports linking the  switches (Trunk ports)

Thank you
Question by:jskfan
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LVL 30

Assisted Solution

Predrag earned 400 total points
ID: 41772132
Yes, on ports between switches. Typically only one of those, since they are pretty similar.

Author Comment

ID: 41772199
Yes, on ports between switches. Typically only one of those, since they are pretty similar.
On Trunk ports Only  ?

Assisted Solution

by:Vincent Zheng
Vincent Zheng earned 100 total points
ID: 41772257
LVL 30

Accepted Solution

Predrag earned 400 total points
ID: 41772330
Yes, on trunk ports only since mechanism both enchansments are using is BPDU. If there is no BPDU on port link will be err-disabled (ports to any device that is not sending BPDU will be error disabled (UDLD will err-disable port only if aggressive mode is configured)).

Author Closing Comment

ID: 41781998
Thank you Guys!

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