Have not done this since moved tunnel endpoint to my pfsense box.. Much better way to do it!! Now you have firewall control at pfsense, etc.
But to allow the tunnel endpoint to be box on lan side of your pfsense box, allow ipv6 traffic and put in the lan side IP address you want to be the endpoint, example 192.168.1.100 or something, whatever the IP of your box is that is going to be the endpoint of your ipv6 tunnel.
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