We want to use dns discover for more than 1000 backends, using udp resolver takes a lot of cpu. I tried the 2.4dev12 branch and the server
key in resolver section solves most of the issue, but same server keyword does not work with 2.4dev17 branch. Is it removed?
The document has it though HAProxy version 2.4-dev10 - Configuration Manual
resolvers mydns
server dns1 127.0.0.3:53
accepted_payload_size 8192 # allow larger DNS payloads
hold valid 10s