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?

[CrimsonLiar]

So using an Asus router on BT my IPv6 WAN address pops up in br0, but the IPv6 gateway address handed to clients (also from br0) is a link-local address.  Worryingly the WAN IPv6 Gateway address listed in the router WebUI is different from what is handed to clients.
Also odd here is that not only do I have my unique web facing IPv4 address, but it appears that I've a CG-NAT IPv4 web address too (I've more details on that but they are irrelevant to this thread)!
*This is on top of discovering that my WAN IPv6 address very occasionally "silently" changes.

[CrimsonLiar]

Unmasked addresses are link local (ie safe - generative and not reachable from the internet)

It's that LAN IPv6 Link-Local address that is being given to clients as the IPv6 Gateway, not the address listed as WAN IPv6 Gateway.

[luc122c]

Hi @mcaddy did you get any further with this? I'm on an openreach FTTP line with a UDM base.
Checking `/var/log/ppp0.log` I see the following (addresses obscured):

peer from calling number XX:XX:XX:XX:XX:XX authorized
sent [IPCP ConfReq id=0x3 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
sent [IPV6CP ConfReq id=0x2 <addr fe80::e985:6fd2:1127:4855>]
rcvd [IPCP ConfReq id=0x64 <addr 212.158.XXX.XXX>]
sent [IPCP ConfAck id=0x64 <addr 212.158.XXX.XXX>]
rcvd [IPCP ConfNak id=0x3 <addr 90.250.XXX.XXX> <ms-dns1 90.255.XXX.XXX> <ms-dns2 90.255.XXX.XXX>]
sent [IPCP ConfReq id=0x4 <addr 90.250.XXX.XXX> <ms-dns1 90.255.XXX.XXX> <ms-dns2 90.255.XXX.XXX>]
rcvd [LCP ProtRej id=0xe4 80 57 01 02 00 0e 01 0a e9 85 6f d2 11 27 48 55]
Protocol-Reject for 'IPv6 Control Protocol' (0x8057) received
rcvd [IPCP ConfAck id=0x4 <addr 90.250.XXX.XXX> <ms-dns1 90.255.XXX.XXX> <ms-dns2 90.255.XXX.XXX>]
Script /etc/ppp/ip-pre-up started (pid 3251380)
Script /etc/ppp/ip-pre-up finished (pid 3251380), status = 0x0

I'm not sure what `Protocol-Reject for 'IPv6 Control Protocol' (0x8057) received` means, or which side is sending that. I've tried DHCPv6 and SLAAC and can't get a prefix from either.

[Ripshod]

If you connect the vodafone router and get an IPv6 then you need to set it up as a "native" connection on your own kit. If the vodafone router doesn't get an Ipv6 address you need to use "6to4" with the ipv4 Anycast Relay set to 192.88.99.1

[luc122c]

Just dug the VF router out of the loft. It doesn't get an IPv6 address. I'm not bothered about using a 6to4 tunnel, i suppose i'll just have to wait a bit longer until they fully roll out native IPv6

[EPicLURcher]

just checking in a few months later to see if you worked this out, as I am trying but am stuck