DNS commands

• dig

  The standard tool for inspecting a domain's DNS records directly, straight from a resolver.

• dig-dnssec

  The `+dnssec` flag: how to check whether a domain is signed and whether its signatures actually validate.

• host

  A fast, script-friendly DNS lookup — one line per record, sensible defaults.

• whois

  Who registered a domain, when it expires, and which registrar or network is responsible.