I have a little complex setup where local my local Pi-hole is using 2 custom upstream DNS servers, which are also custom managed. I have a use-case to add 3rd as the 1st some time go bad together as they are in same cloud. How can i add 3rd custom DNS upstream server.
Edit /etc/pihole/setupVars.conf and add as many servers as you need. Follow the existing pattern.
Then restart FTL - pihole restartdns