If you're running some type of hypervisor (ESXi, Proxmox, etc.), you can create a tiny VM running Debian and load Pi-hole on it. No need for extra hardware and wires.
I run mine on exactly that: a Dell R720 sitting on a rack next to my desk from within a Debian 9 virtual machine inside ESXi.
I actually want to do the opposite: transition this to dedicated hardware (like a Pi, but worried about performance) that is a little less noisy. This is shockingly quiet for a 2U but I am a stickler for silence.
I use ESXi and one of the VMs is pfSense. pfSense has an additional software package called pfBlocker, which is highly configurable and just plan awesome for blockings ads/trackers/etc for the LAN. pfSense has tons of other options - I setup a vLAN and all of my IoT devices are segregated onto it. That way they can't interact with the rest of the devices on the LAN.
Yep... my pfSense is virtualized, too. I need to get pfBlocker configured, but pi-hole works so well, I'm too lazy to do anything about it! I'm also working on an IoT VLAN - that Ring doorbell is a chatty Kathy!
I actually want to do the opposite: transition this to dedicated hardware (like a Pi, but worried about performance) that is a little less noisy. This is shockingly quiet for a 2U but I am a stickler for silence.
Some pix: https://imgur.com/a/0xwcfNN