Upgrade to 21.02 and no IPv6 DNS servers

[immy]

I upgraded my SG-5100 to pfsense+ 21.02 last night.
So far so good.

IPv6 is working.
The strange thing is that pfsense is not showing IPv6 DNS servers on the dashboard like previous versions. (Just using dhcp and dhcp6, no defined DNS)

DNS server(s)
127.0.0.1
202.142.142.142
202.142.142.242

No IPv6 DNS servers.

[viktor_g]

seems related to https://redmine.pfsense.org/issues/11454

[immy]

@viktor_g Possibly. The ipv6 DNS are in the /tmp/igb0_domain_name_server file, but they never get added to /etc/resolv.conf

[viktor_g]

@immy works for me (pfsense 2.5/21.02):
/var/etc/nameserver_v6opt1:

fc00:1234::55
fc00:1234::56

/etc/resolv.conf:

nameserver 127.0.0.1
nameserver fc00:1234::55
nameserver fc00:1234::56
nameserver 192.168.89.5
nameserver 9.9.9.9

Please provide more info about your issue

[immy]

@viktor_g I have a static IP (via DHCP4/6) from my ISP. The IPv4 works with no problems. IPv6 gets an IP ok, but the resolv.conf.never updates.
Rebooted multiple times.
The other day I was looking at the scripts that update the resolv.conf for IPv6.
If I am not mistaken, they only do so if the IP changes.
Which it won't with a static IP.
Although I could be misinterpreting.
I gave up and added the DNS entries via the General Setup to get around this issue for now.