Access Point - path MTU discovery

  • 0
  • 1
  • Problem
  • Updated 3 years ago
  • Solved
Hi, I run into a problem with the AP path MTU discovery.....
Since last week I've problems with remote APs that were running for months but now the radio is off.
After some troubleshooting I've reduced the MTU manualy and now everthing is fine again.


So regarding the path MTU discovery....

- is the path MTU discovery process only performed after a reboot of the AP or every time the AP has no connection to the EWC (i.e. WAN outage / CTP down)

- could anyone please post or PM me the “Tech Note Wireless – MTU Discovery” because as per the knowledge transfer presentation there are scenarios when the network cannot comply with the requirement for the MTU discovery..... and I'd like to know what scenario that is.

Thanks in advance,
Ron
Photo of Ronald Dvorak

Ronald Dvorak, Embassador

  • 51,288 Points 50k badge 2x thumb

Posted 4 years ago

  • 0
  • 1
Photo of Doug Hyde

Doug Hyde, Technical Support Manager

  • 20,710 Points 20k badge 2x thumb
I will send you the document for review. 

-Doug
Photo of Hartmut Sachse

Hartmut Sachse

  • 2,598 Points 2k badge 2x thumb
Hello Doug,

could you send me the documentation, too? One customer have some trouble getting the AP3805i work at a remote site. I'm not sure if some requirements or not met, because i wasn't involved in planning. Only controller discovery work. After some time ap reboots and its starts again.

We have an open GTAC case (01129793). Wireshark traces (captured at the controller) appended show that nothing happens after the RU Discover/RU Response packets between AP and controller). Looks like the answer packets are lost. Customer setup a lower MTU size, but without success. GTAC knowledge base article related to the AP remote site setup would be great.
Photo of Hartmut Sachse

Hartmut Sachse

  • 2,598 Points 2k badge 2x thumb
The world is full of challenges - there are no problems ;-)

Thanks for the fast reply. Mail arrived.
Photo of Hartmut Sachse

Hartmut Sachse

  • 2,598 Points 2k badge 2x thumb
Thanks Doug,

i think the routers are not setup properly for MTU path discovery. Customer have to contact his provide to fix this.