DNS check

The Destination address is the DNS server to query, usually on port 53.

Field	Meaning
DNS name to query	Name whose resolution should be checked
Record type	A, AAAA, MX, TXT, CNAME or NS
Expected response (optional)	An expected response; without a specified value, at least one matching record must be returned

For A and AAAA, the expected address must match the selected IP version. An MX response has the format 10 mail.example.org. TXT checks the exact content. The check returns the number and content of the responses, as well as the response time. It explicitly queries the specified DNS server.