home-assistant
HAOS 16.2 can't resolve cnames anymore
Describe the issue you are experiencing
This started recently but I'm not sure exactly when. I had functioning integrations before and now I've noticed that I have some failing integrations claiming domain names don't exist.
Using a pihole to cname custom1.foo to real.foo for various docker containers, including frigate (eg frigate.foo is a cname pointing at hostmachine.foo). They are properly set up and have been working on all other machines on my network for years.
- ping frigate.foo on a desktop mac: works, shows the correct ip address
- nslookup frigate.foo on a desktop mac: works, shows the cname target, then shows the target's correct ip address, and shows one of my 2 dns servers as the responding server name
- open a terminal in home assistant
- ping frigate.foo: says 'bad address'
- nslookup frigate.foo: says 'server can't find frigate.foo: nxdomain', and shows a random ip address in a random subnet as the responding server instead of one of my actual dns servers
- ha dns info: shows my dns servers in the 'locals' section, but that 'random' ip address is actually listed as the 'host' ip
- settings : system : network ui also shows the correct dns server addresses in the ipv4 section
Note that the same pattern exists for every single cname record that I have defined on my pihole - so now I see that my influxdb integration is down (confirmed in log that it can't resolve the name influx.foo anymore), and all my mqtt things are unavailable which I don't see any errors in its log but is suspicious timing.
What operating system image do you use?
generic-x86-64 (Generic UEFI capable x86-64 systems)
What version of Home Assistant Operating System is installed?
16.2
Did the problem occur after upgrading the Operating System?
Yes
Hardware details
Mac, Parallels 18
Steps to reproduce the issue
...
Anything in the Supervisor logs that might be useful for us?
all entries green, nothing out of place
Anything in the Host logs that might be useful for us?
no dns errors, almost entirely just 'starting time sync, started, stopping' sets and dhcp lease renewal lines
System information
No response
Additional information
No response
With the original settings of
➜ ~ ha dns info
fallback: false
host: 172.30.32.3
llmnr: true
locals:
- dns://10.0.4.1
- dns://10.0.4.110
- dns://10.0.4.111 mdns: true servers: [] update_available: false version: 2025.08.0 version_latest: 2025.08.0
I did a ➜ ~ ha dns options --servers dns://10.0.4.110 ➜ ~ ha dns restart
and now
➜ ~ ha dns info
fallback: false
host: 172.30.32.3
llmnr: true
locals:
- dns://10.0.4.1
- dns://10.0.4.110
- dns://10.0.4.111 mdns: true servers:
- dns://10.0.4.110 update_available: false version: 2025.08.0 version_latest: 2025.08.0
with one of the dns server entries manually added in the 'servers' category the cname responses are coming through? Why was that necessary and what changed to make doing that necessary?