Hi. I have a question. When one fiber is faulty, then the Layer 1 status of the two ports on both switches is going two down, isn't? Why do I need UDLD?
I know this is late but if it’s faulty it doesn’t mean it will necessarily be down. Fiber could be faulty from the carrier but in house your connections are up on both ends.
It is awalys said UDLD take 45 seconds to react to lack of uldl messages (3 times time interval) because it must take the link down BEFORE STP will unblock a port and start forwarding messages (which can create a loop) OK, 3 UDLD messages is 15+15+15 = that is 45 seconds. But you also say when UDLD will not get an answer from its neighbour in 3 hello times (that is 45 seconds) it sends 8 messages, one message per second. And that gives you 45 seconds (3 times 15) PLUS 8 seconds (for the messages sent when there is not response for 45 seconds from the other neighbour) which gives altogether 45+8=53 seconds. STP will react in 50 seconds, 3 seconds BEFORE UDLD will take an action and shuts down a link. So in fact, for 3 seconds there will be a L2 loop, am I right?
Hi, Thank you for Video i have a question, When send to the UDLD packet in aggressive mode, You said every 8 seconds but default value is not 15 seconds? Or did you say 8 seconds to 8 times?
Kevin Wallace video are the best, because he's covering every single topic on his videos
Very clear and simple video tutorial. Kevin makes cisco practically easy to manage.
Excellent video tutorial.. 😊
Great explanation. You have the perfect voice to explain stuff.
That was a great explanation and i like the command to reset all the error disables too!
Great explanation on how UDLD functions. Thank you!!
Excellent explanation Kevin.
Would this work for a uplink port that as a p2p antenna on Ethernet?
Hi. I have a question. When one fiber is faulty, then the Layer 1 status of the two ports on both switches is going two down, isn't? Why do I need UDLD?
I know this is late but if it’s faulty it doesn’t mean it will necessarily be down. Fiber could be faulty from the carrier but in house your connections are up on both ends.
Very clear and crispy explanation... Thank you so much :)
Will UDLD work between two switches connected with L2VPN MPLS ?
I love udld. I Always use it on fibre links between switches.
It is awalys said UDLD take 45 seconds to react to lack of uldl messages (3 times time interval) because it must take the link down BEFORE STP will unblock a port and start forwarding messages (which can create a loop) OK, 3 UDLD messages is 15+15+15 = that is 45 seconds. But you also say when UDLD will not get an answer from its neighbour in 3 hello times (that is 45 seconds) it sends 8 messages, one message per second. And that gives you 45 seconds (3 times 15) PLUS 8 seconds (for the messages sent when there is not response for 45 seconds from the other neighbour) which gives altogether 45+8=53 seconds. STP will react in 50 seconds, 3 seconds BEFORE UDLD will take an action and shuts down a link. So in fact, for 3 seconds there will be a L2 loop, am I right?
Great explanation.😊
Thanks 😊😊
Fantastic!
thank you
Hi, Thank you for Video
i have a question, When send to the UDLD packet in aggressive mode, You said every 8 seconds but default value is not 15 seconds? Or did you say 8 seconds to 8 times?
@@kwallaceccie sorry, i learned English very soon, so i misunderstood.
Thank you very much your reply!!
Awesome!
Excellent description of UDLD.