I have been given a native (no tunneling etc) IPv6 /64 block by my ISP. My pfSense router has successfully got an address, and from its WAN interface I can for instance ping ipv6.google.com and get a reply. However, on my internal network, it does not work, and I can't figure out why. I have a DHCPv6 server handing out addresses, and the router is doing router advertisements, and this seems fine to me.
I'll try to illustrate. Lets say I have a prefix 2001:a:b:c::/64. My router gets it's WAN address using SLAAC, and that becomes 2001:a:b:c:20c:29ff:fef9:b914. On the internal interface, I have assigned it 2001:a:b:c::1 (old IPv4 habit, I guess...). DNS and DHCP is hosted on a server with 2001:a:b:c::10 (static assignment). My workstation then requests an address using DHCP and has been assigned 2001:a:b:c::11ab.
My routing table contains two default (::/0) routes, one for the router's internal static IP, and one for it's link-local IP.
Pinging ipv6.google.com now gives
Destination host unreachable. Where do I start to debug this? It seems to me that it is a routing issue, but I don't know where to start looking.