Ipv6 connectivity for a non-router

I'm running 17.01.4 on a box that is configured as "access point", no router functionality, simply a bridge over the LAN interfaces and the WLAN. In addition, it has dnsmasq-full installed and serves as name server in the LAN.

Up to now, I have used the box for ipv4 only. It has a fixed (static) ipv4 address. But now, I want it to be reachable in the LAN with ipv6 as well. I have tried several approaches with varying success. Here are the problems:

(1) In my network, IPv6 addresses are assigned using RA. This works for all systems, expect for the box. I tried several odhcpd ra-option setting, but my box never got a public ipv6 address. Besides, from the descriptions, this should work without odhcpd anyway. I suppose this is due to the fact that I have configured the interface "br-lan" as static. But it must be static to get the fixed IPv4 address. What I'd need is a "static-ipv4/RA-ipv6" configuration, but this is not in the list. Can I achieve it somehow?

(2) In order to use the box as name server (with ipv6 connectivity) it needs a fixed address. I have assigned a private (fd/8) address to the interface. But the box does not respond to neighbor discovery requests, not even on the box itself (ping -I br-lan ff02::1 | fgrep fdb)

(3) The "real" router in my LAN does not have a "private" (and thus fixed) address. I'd have to configure it as default gateway using the link local address. But openwrt does not accept the syntax "address%interface". (I understand that this would go away if the box accepted the RAs from the router, because they contain the announcement of the default router.)

Any help appreciated.

  • Michael

Have you tried configuring a lan6 interface as dhcp6-client? It should be able to use SLAAC if DHCPv6 isn't available.

1 Like

Can you give me a hint how to do that? How does a lan6 interface relate to my "real" br-lan interface? Is it another interface on the bridge?

I think, I found something. Going to try it tomorrow, thanks.

Lan6 should be an alias. Use ifname 'br-lan' since it's a bridge:

https://wiki.openwrt.org/doc/uci/network#aliasesthe_new_way

New URL: https://openwrt.org/docs/guide-user/network/network_interface_alias