Enabling IPv6 on City Fibre with Unifi UDM Pro

[mcaddy]

My Vodafone FTTP via CityFibre was finally activated on Friday after a 7 week delay. although a little frustrating the compo will be paying for most of my first year so I'm not too upset!

After initially checking all was performing well using the VF router, I got hold of my PPPoE details and swapped it out for my Unifi UDM Pro.

One thing I was surprised to see when I was checking over the VF router config pages was that it appeared to be running Dual Stack IPv6.

I took screenshots of the VF router config before I boxed it back up, so have all the details. The VF config suggested it had a  DHCPv6 /56 prefix delegated. I've tried enabling SLACC and DHCPv6 on the UDM Pro, however, I've yet to get IPv6 working, am I wasting my time? Has anyone got this working?

[Ripshod]

For me it was simple. I use an Asus though, but all I had to do on that was enable 6to4, the rest was filled in automatically when it connected. 

[mcaddy]

Are we talking about the same thing?

I thought 6to4 was a translation mechanism to route IPv6 over IPv4, from what I could see the VF router was operating with native IPv6?

[Ripshod]

Vodafone's "native" implementation of dual-stack will only work on their own routers. If you want IPv6 on anything else it has to be 6to4 for now.

Some time in the future vodafone will enable native IPv6 for all their clients rather than just the new ones, but that is a long way away. It'll also stay restricted to the vodafone router until such time as clients themselves crack the configuration, as we did with digital voice. 

[mcaddy]

Thanks, I'm not bothered enough to do much more at this time, however when I get a moment I shall temp install the VF router and get some PCAP to see if I can spot any further clues.

For now I shall focus on an Asterisk install so that I can get my 'landline' operational, once the further delayed port finally completes!

[CrimsonLiar]

Out of curiosity (I'm with BT now rather than Vodafone), how much of the IPv6 configuration is retrieved by the router from Vodafone's servers, because there's not really that much to retrieve?  Did you try using third-party DDNS servers that will supply IPv6 results from IPv4 servers?
*Going to be using my second-rate scripting abilities later today to tidy up my BT IPv6 DDNS update script, having discovered that very occasionally BT change your IPv6 address but not your IPv4 address, and so the Asus router DDNS update script doesn't fire!  The script I have works, but its so messy I'd be embarrassed to publish it in a forum!

[Ripshod]

That's a really good question. The only configuration I had to do was select 6to4. The "IPv4 Anycast Relay" automatically populated itself (192.88.99.1), then clicked "Apply". Everything else populated itself and IPv6 was active.

As for DDNS I still use the router for IPv4 (no-ip) and run a script on my server for both IPv4 and IPv6 via duckdns. 

[mcaddy]

IPV6 logging in the web UI for Unifi gear isn't great so I thought I'd take a quick look at /var/logs/messages on the UDM Pro, to my surprise when configured for SLAC the UDM appears to be getting a /56 prefix delegation. Relevant log entry below.

2024-01-09T21:08:43+00:00 UDM-Pro ubios-udapi-server[1237]: prefix-delegation: Adding PD prefix to ppp0: 2a0a:????:c3a:c300::/56

However the ppp0 and br0 don't seem to bet getting a IPV6 assignment.

Potentially I'm part way there?

wondering if there was some sort of dependency on MAC addresses, I also thought I would try cloning the MAC of the VF router onto the UDM, that didn't work!

[Ripshod]

You get a /56, I get a /48 for LAN and a /16 for WAN (same subnet).

Settings

[Ripshod]

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