IPv6: router behind router

well… I have a router (VyOS) and behind this router, I’d like to place another router for a sub-range of the IP range (outer router is a /48, inner router a /64). Now… this inner router is a Windows Server… and it doesn’t support DHCPv6-PD (but, I could use the service I wrote to “fix” this on this machine) … what it also doesn’t allow is to modify the link local address (or, I didn’t find out how). Good… the problem now… I have to configure the route on the outer VyOS router. Normally this would be done with a RA package (router advertise)… but, seems VyOS doesn’t accept RA packages and I’ve no idea if it would be possible to configure a DHCPv6 server on VyOS that accepts PD requests.

so… any ideas how to build this? … I can add a static route… but, I cannot be sure that Windows doesn’t change the link local address… I could use “other” static address-ranged to do this, but this would cause other problems… hmm… I know, IPv6 is very new… it’s only getting 26 years old now (if I remember this correctly) so it’s clear, that it’s not yet fully implemeted and supported… but… aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa I’m getting crazy with this stuff…

I found a solution that lets VyOS accept RAs, but… it does use this information and redisributes this directly to other clients… and back to the origin… no nice and causing problems… or… then I have missunderstood what happens here… anyway… still not the solution…

to be honest… this behaviour… the “resend” of the RA that has been received (and not only those that have been statically defined or by DHCPv6-PD)… I think that’s a bug… in the kernel… not VyOS itself… but… that’s just my opinion

You can provide your vyos version and configuration.
In configuration mode:

run show version
run show configuration commands | strip-private

Best regards, Volodymyr Rybak