Resolver: per-request DNS server balancer. Previously, a global server balancer was used to assign the next DNS server to send a query to. That could lead to a non-uniform distribution of servers per request. A request could be assigned to the same dead server several times in a row and wait longer for a valid server or even time out without being processed. Now each query is sent to all servers sequentially in a circle until a response is received or timeout expires. Initial server for each request is still globally balanced.

# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


cat << END >> $NGX_AUTO_CONFIG_H

#ifndef $have
#define $have  1
#endif

END