Ipv6 /64s on vlan-interfaces get wrong gateway

[shebang]

Hello

I have a problem with ipv6 and my vlans:
I have multiple vlans. They all are configured with static ipv4 and ipv6
addresses. IPv4 works perfectly (each vlan has the correct gateway, dns resolutions etc. works).

I have a /64 and a /48 from tunnelbroker.net. When I confgure my LAN
interface to use the /64 it works flawless (I set it up according to
the wiki-article).

But I have a Problem when I try to use the /48 for my network = the lan
interface & multiple vlans.
I set a valid /64 address out of my /48-net as static address on the
different vlans. I disabled dhcpv6 and set the RA to unmanaged (= the
same setup as I would use when configuring just one Netowkr with a /64).

The clients on the different vlans get v6-addresses out of the v6-network for the vlan (e. g. 2001:xxx:xxxx:20::/64 for vlan20 :30:: for vlan30 etc.) but it seems as they do not get the correct gateway. they alway try to route via the gateway of the lan interface which does not work.

On the lan interface, everything works as the ipv6-gateway could be reached without problems.

What can be the issue here? Do I always need dhcpv6 when using multiple /64 subnets out of a /48?

Thanks!

[jimp]

You'll need to provide a lot more detail about the specifics of how you set everything up, including DHCPv6 and RA tab settings for each interface/VLAN

I have a similar setup (HE.net /64 and routed /48) and I use subnets from the /48 on VLANs and they work perfectly.

Something about your interface/DHCP/RA setup or even your switch/L2 must be not quite right.