DHCPv6 LAN through DHCPv6 client on WAN6 setup

I have connected my ISP's modem/router on the WAN port of my router. I haven't changed the modem's configuration, so on WAN my router acts like a DHCP and DHCPv6 client. Currently on br-lan, a bridge of the LAN ports and Wifi, I have set a static IPv4 IP, with a different network part than my ISP modem. If I go in Network > Interfaces I can see both WAN and WAN6 working correctly.

Screenshot%20from%202018-12-24%2015-40-35

With DHCPv6 enabled on br-lan I only get link-local addresses on my network. I would like to be able to get ULAs for my network devices. I'm new to IPv6 and a bit unfamiliar with all the terminology so I'm not sure what the correct configuration for the DHCPv6 section is.

Checking on Status > Overview I can see that even if the WAN6 DHCPv6 client seems to have gotten a ULA, the information on the IPv6 Upstream differs.

Link to the IPv6 upstream thing because as a new user I'm limited to one image per post.

What I want to do is offer a DHCPv6 server which can assign ULAs like WAN6's correctly to its devices. I want to avoid using my modem's DHCPv6 except for the WAN6 connection where my router acts as a client. I'm pretty unfamiliar so this might not even be possible, please advise me if this is the case.

Here's the incorrect IPv6 upstream.
Screenshot%20from%202018-12-24%2015-47-02

  • The upstream is not incorrect.

Now, to get a ULA:

Screenshot%20from%202018-12-24%2009-10-41

How come it's correct? It doesn't match WAN6, while IPv4 upstream matches WAN. Should it not?

I set the assignment length but I'm still not getting a global address. This is what my DHCPv6 settings look like.

Screenshot%20from%202018-12-24%2016-57-28

I thought you were concerned bout the ULA.

If you are concerned about an upstream IPv6 Global addresses instead, please provide the information from your upstream provider. You will need to statically assign Public IPv6 downstream, or verify your ISP issues a subnet larger than /64.

ULA is not the same thing.

I'm sorry I got confused, I meant to say GUA. As I said I'm pretty unfamiliar with this. Unfortunately I don't have any information from my ISP. Is there any way short of asking them to find out which subnet they assign to customers?

Sure. The upstream router you're referencing (192.168.1.2) should show you the IPv6 subnet size issued to its WAN interface.

You mean 192.168.1.1, right? The only information I can find there about the address space is in the routing table.

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