In pihole I provisioned the FQDN of a device on my local network with its local static ip address using the "Local DNS" page under the "Tools" menu. The provisioning succeeded. I see the provisioned key-value pair in /etc/pihole/custom.list. I then flushed the cache and restarted DNS. In /var/log/pihole.log, I see the resolver sometimes using custom.list to retrieve the desired ip address, but sometimes it forwards the request to the upstream server(s). In the "Query Log" of the web interface I see the requests for the local device going to the upstream servers. The requests come from multiple clients on my network.
Debug token https://tricorder.pi-hole.net/TnVpuy0M/
(The local device is "family-room-apple-tv.openthread.thread.home.arpa")
Resolution should default to local DNS first, and iff that fails go to upstream
Details about my system:
Linux pihole 5.10.63-v7+ #1488 SMP Thu Nov 18 16:14:44 GMT 2021 armv7l GNU/Linux