I originally installed pihole on my rpi4b and set it up to get it's IP address via DHCP, but I set that DHCP lease as static on my router which I was still using as the DHCP server.
I then realised that meant my router was the only device querying the pihole so it made analysing query origins impossible.
So, I switched the DHCP server to the pihole and configured the eth0 network device to have a static IP, for the DNS configuration on the interface I used 127.0.0.1
It works, but on the pihole dashboard, localhost is the top of the query leader board, and clicking into it shows hundreds of .arpa DNS requests.
I have unbound running on port 5335 which the pihole is configured to forward requests to.
Have I misconfigured something here? I feel arpa dns lookups from localhost should not be going via the pihole.
Should I set the interface dns address to point to unbound directly - or is there another recommended setup?
It turns out NetworkManager and /etc/resolve.conf do not support having custom ports for the DNS configuration so I can't redirect traffic to my unbound service without doing some iptables magic - and I'd rather not have that complexity.
For now I've set the interface back to using cloudflare which is not ideal but I don't want to have a dedicated box to just host unbound in.
Something is definetly wrong in your setup. I would sugggest going to Tools > Generate Debug log and upload a debug log. Post the link to the log in comments so a dev / moderator can take a look.