I'm running pihole on a Docker Container, and have unbound installed in the docker host. After searching this forum, I've found out that I can't just simply point the upstream dns server to 127.0.0.1#5335.
Which address should I use as my upstream server on pihole, so that it will properly use unbound on the docker host? I'm sorry for the noob question, but this is all new to me.
The 127.0.0.1 loopback address would point to the machine that Pi-hole is running on.
When running a dockered Pi-hole, that would be the Pi-hole container.
As unbound is running on the host system, you should configure that host system's private IP address as Pi-hole's sole upstream.