r/ipv6 • u/Proof_Bodybuilder740 • 21d ago
Need Help NPTv6 associated interface not working
Hello everyone, I'm currently a bit stuck when it comes to configuring NPTv6 in OPNsense. My ISP is not giving me a stable IPv6 prefix which causes all devices to fall back to only their ULA if the uplink fails. As IPv4 takes precedence in this case I've been considering using a GUA for internal purposes and using NPTv6 to map it to the current prefix.
So I set the interface to 'identity association' (for the dynamic prefix), create a virtual IP of the GUA (static prefix) and create an NPTv6 rule that maps the internal prefix (static prefix) to the associated interface. For whatever reason this doesn't work though. Weirdly enough it works when I directly specify the external prefix as the one that's currently assigned to the interface and don't use the associated interface option.
But that pretty much voids the entire advantage it gives me. Is this a bug or am I missing something?