Post #1695156

@dbauer @tykling Testing local DNS config (or I will say "local resolution config" because names can be resolved in many ways, static /etc/hosts being one) is related but slightly different from testing DNS (purely) by doing DNS queries. To test local resolution config I would advise more towards using `getent ahosts` or `resolvectll`. Or any language piggybacking `gethostbyname` and similar libc endpoints.