The Internet Mail Service DNS Resolver Test performs a DNS query for MX records that match the specified domain. A list is created of one or more IP addresses in the same order of preference Internet Mail Service uses in its attempt to deliver mail for that domain.
If the MX query returns no results, a query for the A record matching the domain is performed. The result is a single IP address. If the A record search returns no results, the host file on the local computer is checked. If a match is found, the result is a single IP address.
The DNS Resolver Test is useful for checking DNS or host file configurations and for troubleshooting delivery problems.
Run the Internet Mail Service DNS Resolver Test from the Support\Utils directory on the Microsoft Exchange Server compact disc. Run the test from the same computer that runs the Internet Mail Service after TCP/IP and DNS are configured.
To run the IMC DNS Resolver Test with options, type the following at the command prompt:
restest [-debug] domain
Using -debug causes additional information to be displayed at each step of the search.