HA spamming PTR DNS lookups?

Configuration
103

I’ve been investigating this, working to tie together multiple threads from github, reddit and HA community on the cause and options to fix

This is sort of the short summary as I understand it:

  • it’s a feature not a bug :wink: , albeit viewed as overly aggressive by most
  • HA is scanning your LAN for new devices to add
  • When you see a “new device has been found, would you like to add it?” in your HA settings, it was discovered through these scans

Ideally, it would be nice to have an HA parameter or configuration change that rate limits the number of DNS queries (X/hr) to a more reasonable number that limits HA and Router CPU and network bandwidth.

Here’s additional background

  • DNS query burst after upgrade · Issue #139957 · home-assistant/core · GitHub

  • HA uses DHCP module, which is looking for new devices on your LAN (subnet)

  • reverse the IP address numbers in the error message - (192.168.X.Y) is your LAN IP pool.

  • Sometimes HA gets carried away after an update, increasing the number of scans/hour; that may be what happened recently (Oct 2025)

  • It can be stopped by disabling one or more features of HA, including DHCP

  • BUT you may break things in future updates, others have done this and forgot to check when they experience other issues (especially when HA can no longer auto-discover new devices)

See additional posts on disabling DHCP and other modules
- HA spamming PTR DNS lookups? - #67 by alvarobas
- [DHCP] add configuration options

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