Cascaded Router: IPv6: LAN mode: Native?

My GL.iNet White (GL-AR150 with firmware 3.201-release) runs in the factory-default Internet mode: Cable WAN. My White is located behind an existing IPv6 enabled router which offers DHCPv6-Prefix-Delegation (DHCPv6-PD). It is very much the same setup as in this thread. My White is a router behind another router.

In the GL Web interface, the IPv6 WAN part is quite obvious: Address Type = Automatic. However, when it comes the LAN part, I am offered ‘Native’ and ‘NAT6’. The latter is described in the OpenWrt wiki … Therefore, I went for ‘Native’. That does not do the trick either because the IPv6 Router Advertisements of the upstream router are just forwarded. Consequently, my LAN client creates an IPv6 with the wrong prefix ID.

Then, I looked into UCI: The script /etc/init.d/gl_ipv6 puts the deamon odhcpd into relay mode. After changing

uci set dhcp.lan.ra_management=0
uci set dhcp.lan.ndp=server
uci set dhcp.lan.ra=server
uci set dhcp.lan.dhcpv6=server
uci commit dhcp
service odhcpd restart

my GL router works as expected. While tracing the network traffic in Wireshark, I see that the GL router is asking for a IPv6 prefix in the upstream router, via

ifstatus wan6

I see the correct IP address, prefix, DNS, and route being assigned. And my LAN client gets its IPv6 address in the expected prefix via the IPv6 Router Advertisements and the GL router itself as DNS server via stateless DHCPv6. All I had to do, was to edit the script, so this survives reboot.

Long story short
Why maps the LAN mode ‘Native’ of the GL Web interface to ‘relay’ in odhcpd? I still have to test the mode ‘Cable LAN’, whether it is correct there. At least when the GL router is in the mode ‘Cable WAN’, should’t it default to ‘server’? If not, can we get an additional mode beside ‘Native’, ‘NAT6’, and ‘Static IPv6’ in the GL Web interface? Not sure how to name that one because I expected that to be the default.

Does the issue solved in this post?

Not sure whether I understand the question. That other thread/post is about the mode ‘Access Point’ (Cable LAN). This thread/post here is about the mode ‘Router’ (Cable WAN). I use ‘two’ GL-iNets if you like to say so. In router mode + IPv6 native mode, GL.iNet is using ‘relay’ and I do not understand why. Even if I would understand, I need ‘server’ as changed above.