I had also the same issue. I found a hack to disable the PTR DNS lookups.
I installed this addon in HA.
https://github.com/tronikos/default_config_disabler
Then from the configuration of the addon, I just disabled the dhcp
This stopped all the PTR DNS lookups.
Just to add that I installed homeassistant for the first time in a docker container a few months back.
Later I noticed that I was having strange DNS resolution failures. Turns out I was being blocked by quad9 DNS because HA was doing a PTR query for each IP in the local address range, exactly once an hour, all within a few milliseconds.
Too bad this is still not fixed by default after all these years.
This worked for me. Thanks so much. If I want to have HA auto-discover new integrations I can easily enable and then disable dhcp from this integration.
That solved it for me. Disabled DHCP as suggested by @jgmGit and added -n parameter to nmap tracker. The requests finally stopped. Thanks everyone.
Well so far it definitely stopped my PTR requests. Just two HINFO IN ā¦ REFUSED now, not sure what that means.
Well a few more than two. I donāt run pi hole or anything. Unify UDM is my router.
This started happening to me after installing 2025.3
Now I get a PTR request of the ip range each hourā¦
Iāll try disabling DHCP in the default_config like people suggested.
It starts around 20:00 when I installed the new version, and then the hourly spikes:
And the requests:
Yep, same here. Never had this issue before, suddenly started after updating to 2025.3
And another one here - Iāve never seen this before 2025.3. Since then Iāve been logging around 260-270 PTR queries every hour from HA, looking at IPs on my LAN. A few hours ago I used the Default Config Disabler to disable the DHCP integration, as suggested further up the thread, and that seems to have stopped the queries - so far so good.
One of the past updates also triggered the hourly PTR wave on my HA installation (RPi).
Disabling the dhcp integration proved to solve the problem, I verified it by re-activation and the problem reoccurred.
Disabling default_config creates the issue, that if a future update changes the default_config the HA installation will not pick up on it, if you create your own config. Youāll have to remember changing this - which I didnāt want to.
The solution that worked for me is this: GitHub - arturpragacz/hass-cc-default-config-exclude: Exclude components from Home Assistant Default Config
This allows something like this:
default_config:
default_config_exclude:
- dhcp
none of the IPs from my PTR log (reverse DNS queries) appear in my active device list.
Iāve just noticed this happening from my Home Assistant 2025.7.1 in my Adguard Home logs - why hasnāt this issue been properly resolved all this time??
Iāll try the default_config/dhcp suggested fix, but what else is likely to break when I disable HA dhcp?
UPDATE: Iām still waiting to see if disabling dhcp has resolved the issue on my rpi5 HAOS, but in the meantime, Iāve now noticed my ābackupā HAOS on my old rpi2b (also 2025.7.1) is now spamming Adguard Home with hundreds of reverse DNS lookups! This issue needs resolved ASAP!
Did disabling dhcp work? Iām getting hammered by āin-addr.arpaā
It does work short term but always seems to come back in my case.