Thanks for making this connection, @overbored!
I performed a packet capture again. My phone makes no attempt to establish the VoWiFi tunnel over IPv6.
It only performs a DNS query for the ePDG's A record, not AAAA. Then there's absolutely nothing after the DNS reply.
It doesn't matter whether I filter A records in Unbound or not (AAAA-only mode).
It really seems that my phone's VoWiFi stack is strictly IPv4-only and doesn't attempt to use Android's CLAT either.
This might be different with other / newer phones like your iPhone.
@bestboy, would you mind testing this Tayga setting with your phone?
Cheers
Maurice
I performed a packet capture again. My phone makes no attempt to establish the VoWiFi tunnel over IPv6.
It only performs a DNS query for the ePDG's A record, not AAAA. Then there's absolutely nothing after the DNS reply.
It doesn't matter whether I filter A records in Unbound or not (AAAA-only mode).
It really seems that my phone's VoWiFi stack is strictly IPv4-only and doesn't attempt to use Android's CLAT either.
This might be different with other / newer phones like your iPhone.
@bestboy, would you mind testing this Tayga setting with your phone?
Cheers
Maurice
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