Routing and prefixes

[johnantypas]

I know this has probably been asked many times before -- and I'm getting there honest!

I've got my tunnel up and I can successfully ping6 the far end. I'm using a /64 routed space.
I've also got local machines pinging the router on their on /80 space.  (Right?)  It seemed to me that if I was offered a /64 of
a:b:c:d::/64, I could just use a:b:c:d:1::/80 for internal nodes.  I also gave this number to Radvd.

Everything works except when I try to leave the subnet.  In IPv4, it's a default route and IP forwarding problem.  Here, I get address out of scope on a ping6.  My thoughts, such as they are :-) were that:

If the local nodes were ::/80, and they had a default route ::/0 to the router it woudl pass things on to the tunnel.
On the way back, given everything is global, traffic should flow back to the ::/80.

It doesnt.  What have I missed?

[kristiankrohn]

"Normal" setups use /64s as subnets. Especially autoconfiguration requires a /64.

If you only got one routed /64 and want to use autoconfiguration, you can only use one subnet.

Edit:
FYI, RFC 1972 was obsoleted by RFC 2464. (Therefore 64 bit host addresses are required for autoconfiguration on ethernet.)

[kriteknetworks]

Is ipv6 forwarding enabled on the gateway machine?
Since radvd requires /64, are the LAN machines actually GETTING an IP in your /80?