IPv6 mismatch

Problem with Beta 5.0:
The ipv6 address in Settings -> System does no match the ip i get when i use ssh -> ip add

My system is Ubuntu server 18.04.4 and fully upgraded
Pi-hole Version vDev (release/v5.0, v4.3.5-450-g1b35eeba) Web Interface Version vDev (release/v5.0, v4.3.2-437-gbc9c656e) FTL Version vDev (release/v5.0, vDev-603507c)

Debug Token:

Your debug log indeed shows no IPv6 address match, but also no IPv6 connectivity at all (click for details)
[i] Default IPv6 gateway: fe80::xxxx
[✗] Gateway did not respond.

*** [ DIAGNOSING ]: Name resolution (IPv6) using a random blocked domain and a known ad-serving domain
[✓] sale.tumblr.com is :: via localhost (::1)
[✗] Failed to resolve sale.tumblr.com via Pi-hole (2a00:fd00:fff4:a0e8:e23f:9c32:7d54:b0c9)
[✗] Failed to resolve doubleclick.com via a remote, public DNS server (2001:4860:4860::8888)

Likely, your global IPv6 address has changed since you installed Pi-hole (as is common for IPv6 privacy extension addresses).

As stable address assignment is mandatory for Pi-hole to work, you should consider using a ULA address instead, see Use IPv6 ULA addresses for Pi-hole.

Once assigned a ULA prefix, you’d have make Pi-hole aware of its new ULA address by running

pihole -r

and choose reconfigure.

I got the same IPv4 for over 1 ½ year and my ISP is using IPv6rd
Does IPv6rd not depend on your IPv4 address ?

I don’t think that my Zywall USG support ULA

A single global IPv4 address, as assigned by your ISP, would identify your router. While it is true that the corresponding complete IPv6 address is somehow derived by your IPv4 address when IPv6rd is in effect, exact mapping procedures would depend on your ISP - but again identifying only your router.

All other devices in your network are assigned a private IPv4 address (commonly by your router) and may construct an IPv6 address by combining your IPv6 prefix (as provided by your ISP) with an interface identifier (as calculated by the device itself).

If your router does not support ULA prefix assignment, you could try and use your Pi-hole machine’s non-routable(!) link-local IPv6 address (from fe80::/10 range).

Note that devices need to be within the same network segment for this to work, i.e. commonly all devices need to connect directly through your router - any L3 switching will prevent devices connected through such a switch/router/AP to see and communicate with Pi-hole’s link-local address.

Thanks for the help so far