Why so many ptr lookups? PiHole is getting hammered!

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    PiHole 4.1 now shows all requests, I can ignore them but I feel this is and must have been impacting my PiHole for a while now. Really this explains some DNS issues.

    I tried pausing all iOS devices and killing guest wifi with no change.

    1669828 requests.


  • @michaele What is the source address of these numerous DNS queries? Could you please generate support files and send them in so we can investigate? We have seen this once before but the traffic was not coming from AmpliFi rather it was between a client and the PiHole.
    Please reference this community post when you send in your support files please.

  • @ubnt-brett yes. I'll re-enable conditional forwarding (I like seeing the hostnames lol) on the pihole tomorrow and once I see it start back into it's loop I'll capture the support log and send it in.

    Source is the router, the main meshrouter in my group. It seems the router gets the request and passes it to pih. Then pih configured for conditional forwarding sends it to the router. It looks like a loop but I enabled dns-loop-detect (dnsmasq) on the pih with no change.

    I wonder if we need more controls once DNS cache is disabled. Like since the router is the dhcp server, don't forward reverse lookups? Should be an option, I imagine others may want ptrs forwarded.

  • @ubnt-brett ok I emailed a support file in.

  • Hey @michaele your PiHole is configured to use AmpliFi as DNS server. This causes DNS request loop. PiHole must be configured to use or any other external DNS. Can you modify your configuration and let me know the results?

  • @ubnt-brett yes with conditional forwarding turned on it asks the router for reverse lookups, otherwise I get only IPs in the pihole stats. If Amplifi is the dhcp server why is it forwarding reverse lookups to the configured DNS server?

    Can it be configured to not forward local lookups if bypass DNS cache is enabled? I guess I don't think it should at all.

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