@Clive_A 

I have already added all possible rules and combination in mDNS. It is not working. 

  @Clive_A 

Thanks! I will respond to the ticket raised.

  @Tapwater Hi there. Was there any kind of answer to the ticket? I have a similar problem. ER7212PC via EAP 660 HD with Sonos. Result after 5 hours googling, finding several supposed fixes and just trying to work it out... Result: Apparently impossible. So I actually also assume that it might have to do with the ER7212PC.

I know Sonos is a huge problem in general. But still I am disappointed in the TP link equipment.

I guess it might come down to this: https://www.youtube.com/watch?v=oFtAX8tGnEI

Thanks for the response!

I worked through the troubleshooting guide already. In all fairness I just did not wireshark the actual mDNS transmissions assuming that the information about Sonos when it comes to mDNS is already out there in the internet and presumably reliable.

My scenario:

• ER7212PC v1.0 (Firmware 1.1.1)
  • VLAN 10
    • EAP660 HD(EU) v1.0 (Firmware 1.2.9) (wired to Port 12)
  • VLAN 20 (Main)
    • Cellphone (connected through WLAN on EAP 660HD)
  • VLAN 50 (IoT)
    • Sonos Speakers (connected through WLAN on EAP 660HD)

=> When I open the Sonos app on my cellphone it says it cannot find the Sonos system.

When I change the cellphones VLAN for testing purposes into 50 (same than the Sonos) it immediately works.

So plain and simple that to me is verification that the crossing of the vlan causes the problem.

That is very well documented all throughout the internet.

So far so "expected".

To exclude any potential mishaps I deleted all ACLs.

I then added a Profile -> Bonjour Service by the name of "Sonos" with Service ID "_sonos._tcp.local"

Lastly I added the mDNS within the "Services":

And that's when I would expect it to work but unfortunately doesn't.

And just to be clear: Browsing through the internet Sonos seems to be a pain in the a**... So I am not entirely sure if I did something wrong, if Sonos is just to awkward or if the ER7212PC is not supporting a needed feature or whether there might be a bug.

  @Clive_A  @Markus123 

I have never agreed with your assessment of the issue but choosen to ignore since I decide to move away from this ecosystem eventually. 

The issue is caused by ACL defined at the Gateway (which is the router) whereby I am attempting to block connection between the various vLAN e.g. IOT towards General/Public. 

Even if I were to add permit rules that is specific to Airplay & MDNS, it will not work at the gateway level. 

The only way this will work is if I disabled Gateway level ACL which basically imply that there will be no access control between the VLANS. 

So yes, it will work since you have to basically disable all ACL (even if there are exceptions or permit rules setup). I just have to comment to make sure others have a clearer picture of the bad product design of ER7212PC. 

For those who are interested to know more about the issue that is considered resolved, please read https://community.tp-link.com/en/business/forum/topic/620638