In the Domain Name System (DNS), the process of a resolver sending a request to a name server. The resolver sends the host name of a TCP/IP host on the internetwork, and the name server returns the host’s IP address. The name server is said to “resolve” the name of the host into its associated IP address.
The query sent by the resolver to the name server is most often a recursive query, which returns either the expected IP address or an error. This type of query makes it possible for a name server to forward the request on to other name servers if it can’t resolve the name and then return the result of that request to the resolver. If the queried name server is configured to forward requests, it can perform an iterative query, querying several name servers in succession until it resolves the name or runs out of name servers to query.