According to pgbouncer README.md file c-ares is the prefered way to resolve names for pgbouncer 1.10+: https://github.com/pgbouncer/pgbouncer/blob/master/README.md#dns-lookup-support The previous method (evdns) did not support EDNS0 and SOA lookups.
According to pgbouncer README.md file c-ares is the prefered way to resolve names for pgbouncer 1.10+: https://github.com/pgbouncer/pgbouncer/blob/master/README.md#dns-lookup-support The previous method (evdns) did not support EDNS0 and SOA lookups.