So it's come down to two things:
- The
ServerIP
environment variable has to be set on the pihole docker container. (It should be set to the LAN IP of the machine that the container is running on.) - Even with this fix, the router's DNS is intercepting the request to pi.hole. That is, if I set
/etc/resolv.conf
to use the pihole box directly, http://pi.hole resolves fine. But if I set it to the router's IP, and configure the router to use the pihole box as the DNS, then it fails. So, at this point, it looks like a DD-WRT issue, and I'll go ask on their forums.
Considering this issue fixed. Thanks again for the insight!