UDLD timers

[sebastien3]

Hello,

I'm trying to find a best-practice for using UDLD port aggressive with fast-hello and message time but I can't find much...

What is the recommended value for udld fast-hello (200-1000 ms) and udld message time (1-90 s) ?

Thanks

[MHM Cisco World]

Keep timer as defult dont modify it.

I recommend not modify any defualt timer.

[sebastien3]

The default timer are too high ? No ?

UDLD will send each ither hello packets every 15s. If the responses are missing, switch disabled the port.

This means that for 15s the whole network will be cut so that STP decides to switch to another path...

[MHM Cisco World]

You mention fast udld and it message interval (defualt) 200 ms

This for me so enough to detect link failed.

[sebastien3]

200 ms is also for me a good value, but not being sure I prefer to have an opinion !

udld message time maybe 1s

Output of my switch :

Port enable administrative configuration setting: Enabled / in aggressive mode
Port enable operational state: Enabled / in aggressive mode
Current bidirectional state: Bidirectional
Current operational state: Advertisement - Single neighbor detected
Message interval: 200 ms
Time out interval: 5000 ms

Port fast-hello configuration setting: Enabled
Port fast-hello interval: 200 ms
Port fast-hello operational state: Enabled
Neighbor fast-hello configuration setting: Enabled
Neighbor fast-hello interval: 200 ms

Entry 1
---
Expiration time: 600 ms
Cache Device index: 1
Current neighbor state: Bidirectional
Device ID: JAE47537G3V
Port ID: Te1/1/4
Neighbor echo 1 device: JAE899807KP
Neighbor echo 1 port: Te1/1/3

TLV Message interval: 1 sec
TLV fast-hello interval: 200 ms
TLV Time out interval: 5
TLV CDP Device name: switch-1.internal.test