MDNS response broadcasts not received
I'm trying to troubleshoot MDNS (bonjour/airplay) communications and am running into an issue. The client that is hosting an airplay service is receiving the broadcast request and is replying but the response is never received by the pfsense router. I have run a packet capture on both the client device and the pfsense box. On the client I can see the broadcast request come in and then a broadcast response is sent. However, on the pfsense box, I can see the broadcast request but I never get the response.
I have attached screen shots from Wireshark of packet captures of the same time frame from both the client and pfsense.
client -> 192.168.5.102
pfsense -> 192.168.5.1
Both devices are directly connected with no routers/switched between them. I have the standard LAN pass to all firewall rule enabled and I do not see any traffic being blocked. There are no firewalls or rules on the client that would be preventing outbound traffic. I'm at a bit of a loss why the pfsense box can not see the broadcast response.
If the two devices are on the same subnet, then pfSense won't see the replies. It only sees the broadcast because it's broadcast. Otherwise the firewall won't see any direct client-to-client communication inside a subnet. That is all handled at layer 2 by your switch or wireless access point.
If you have a wireless access point and both devices are wireless clients, make sure the AP does not have client isolation active which would prevent the two clients from reaching each other.