Recursive lookup

If a DNS server cannot answer a query because it does not contain an entry for the host in its database, it can recursively query DNS servers higher up in the hierarchy.

This is typically how Internet applications making DNS queries work. For example, a web browser always specifies recursive lookups when it is attempting to resolve the host portion of a URL.

Non-recursive lookups present a more accurate picture of how the DNS server is performing, whereas recursive lookups give a better indication of the DNS performance that Internet applications (and therefore users) are getting. The DNS monitor supports both recursive and non-recursive lookups.