Migrating this feature request from GitHub:
I’d love to see the option of running multiple PiHoles in your network and a means to keep all of them in sync (whitelists, etc). Ideally, only one would serve the Web Interface, and it would show stats for multiple PiHoles. (the other PiHoles could be “satellite” PiHoles or something)
The use case is the following: I have PiHole running flawlessly in an Ubuntu Server 16.04 VM in Hyper-V. But this is a single point of failure - when I reboot my Hyper-V host for updates, for example, the PiHole goes down. I want to implement a Raspberry Pi as well, so clients have a “backup” DNS that’s also a PiHole. As it stands now, the backup DNS servers are just Google’s 18.104.22.168 and 22.214.171.124, but I’d love the opportunity to make more PiHoles and minimize management overhead.