Hey Kentzo,
Turns out you're right, and I was wrong. I've turned off IGMP snooping, as it doesn't help after all (like you say, it has the potential to hinder).
I have multiple VLANs, and all of them run IPv4 and IPv6. I have homepods, an Apple TV and Sonos speakers in an IOT VLAN and my phone and Macbook in a trusted VLAN. Airplay (or rather Apple Music streaming via Airplay) sometimes worked, sometimes didn't. I have an mDNS repeater between the VLANs and the DNS entries make it across (There's an excellent mDNS browser called Discovery in the MacOS Appstore)
After deploying Wireshark, turns out the dual stack plays a role: when the Macbook is on Wifi, Airplay uses IPv4. When it's on a wired connection, it uses IPv6. Airplay over IPv4 works, over IPv6 it doesn't. It seems to break soon after it receives an mDNS reply for RAOP (Remote Audio Output Protocol), which is a different service to AirPlay. I guess Airplay is for streaming from a device to a speaker, RAOP is for when the speaker plays a source by itself (Apple Music) under the control of another device.
I'm still trying to figure out what is going on, but one theory is that RAOP uses the link local IPv6 address from a device on another VLAN, instead of its local or globally routable one (my VLANs run a private range and a public one obtained via prefix delegation)
I got confused because it sometimes worked and sometimes didn't, and switching on snooping seemed to fix it. Turns out i was sometimes trying it with the wired connection plugged in, and sometimes without (it would be on wireless, hence IPv4, hence working)
IGMP snooping and MLD (it's IPv6 friend) are meant to help reduce multicast traffic by having the MikroTik send it only where it is needed, not every port. Ubiquitu has the same, but in some older firmware versions with it switched off multicast Neighbour Discoverey messages also got dropped, breaking IPv6. That's no longer an issue. So yes, IGMP snooping doesn't fix AirPlay.
As far as I can tell, other than mDNS, AirPlay itself does not use broadcast or multicast in any way, it's all unicast. Which is why I'm stumped as to why it doesn't work on IPv6 - unless it's using link local addresses instead of routable ones.
Turns out you're right, and I was wrong. I've turned off IGMP snooping, as it doesn't help after all (like you say, it has the potential to hinder).
I have multiple VLANs, and all of them run IPv4 and IPv6. I have homepods, an Apple TV and Sonos speakers in an IOT VLAN and my phone and Macbook in a trusted VLAN. Airplay (or rather Apple Music streaming via Airplay) sometimes worked, sometimes didn't. I have an mDNS repeater between the VLANs and the DNS entries make it across (There's an excellent mDNS browser called Discovery in the MacOS Appstore)
After deploying Wireshark, turns out the dual stack plays a role: when the Macbook is on Wifi, Airplay uses IPv4. When it's on a wired connection, it uses IPv6. Airplay over IPv4 works, over IPv6 it doesn't. It seems to break soon after it receives an mDNS reply for RAOP (Remote Audio Output Protocol), which is a different service to AirPlay. I guess Airplay is for streaming from a device to a speaker, RAOP is for when the speaker plays a source by itself (Apple Music) under the control of another device.
I'm still trying to figure out what is going on, but one theory is that RAOP uses the link local IPv6 address from a device on another VLAN, instead of its local or globally routable one (my VLANs run a private range and a public one obtained via prefix delegation)
I got confused because it sometimes worked and sometimes didn't, and switching on snooping seemed to fix it. Turns out i was sometimes trying it with the wired connection plugged in, and sometimes without (it would be on wireless, hence IPv4, hence working)
IGMP snooping and MLD (it's IPv6 friend) are meant to help reduce multicast traffic by having the MikroTik send it only where it is needed, not every port. Ubiquitu has the same, but in some older firmware versions with it switched off multicast Neighbour Discoverey messages also got dropped, breaking IPv6. That's no longer an issue. So yes, IGMP snooping doesn't fix AirPlay.
As far as I can tell, other than mDNS, AirPlay itself does not use broadcast or multicast in any way, it's all unicast. Which is why I'm stumped as to why it doesn't work on IPv6 - unless it's using link local addresses instead of routable ones.
Statistics: Posted by robbiereindeer — Tue Mar 12, 2024 12:52 pm