Hi  @daniel_hainich 

Thanks for posting here.

Thank you for your feedback. We need to understand how your topology is actually connected. Or do you have a topology from the 5.15.24?

Additionally, could you confirm whether LLDP is enabled on the device? Thank you.

Hi  @daniel_hainich 

Thanks for the picture. 

Did you try to reboot the system? did it help? Please reboot the devices according to the following order:

router > uplink switch > controller > EAP > mesh EAP

One more question, where is the controller plugged to? the core switch?

  @daniel_hainich 

Thank you so much for taking the time to post the issue on the TP-Link community!
To better assist you, I've created a support ticket via your registered email address and escalated it to our support engineer to look into the issue. The ticket ID is TKID251150341. Please check your email box and ensure the support email is well received. Thanks!
Once the issue is addressed or resolved, please update this topic thread with your solution to help others who may encounter the same problem as you did.
Many thanks for your excellent cooperation and patience!

Hi  @daniel_hainich 

How is the behavior these days? 

We suspect this may related to the LLDP on the ALE Switch OS6360-P24.

Would you please disable LLDP forwarding for the ALE Switch OS6360-P24 and see if it helps?

Hi  @OMADA-tunisia 

Thanks for sharing the solution.

Would you please share a screenshot of your topology so we can better understand it? Thanks.

OMADA-tunisia wrote

Same problem with my setup. And no solution even with the latest omada update The only solution I have found is disabling LLDP-MED on the default profile and assign it to access port Keep the "all" profile with LLDP-MED enabled and assign it to uplink port

Hi  @daniel_hainich 

Thanks for sharing and glad to hear that you have found a solution.

This is most likely because there are other devices in your network capable of forwarding LLDP, such as the ALE Switch OS6360-P24 you mentioned.

@OMADA-tunisia 

Can you please help us confirm whether the involved SDN devices are plugged into a third-party device that supports LLDP forwarding?

daniel_hainich wrote

after i disabled the lldp for all AP´s (network config->site settings->eap lldp) my topolgy is ok. after enabling it again, topology is broken. so its something wrong with lldp calculation with the AP´s.