u/Apprehensive_Swan662

Currently I have my 3 pihole instances on their own vlan and all other vlans such as my main, iot, and guest vlan can only connect to it via port 53 so that the dns traffic routes through them. I have recently be tihnking about making some changes to my network and was wondering if I shouldnt just let the guest and iot vlan use something like quad 9 be its dns and move my pihole into my main vlan, making that be the clients using it. I guess I am just curious if its slightly redundant since my guest and IoT are already isolated.

Thoughts, tips, suggestions?