Using the dcdiag command. The DCDiag (Domain Controller Diagnostic) tool will analyze the state of the domain controllers and services in an Active Directory (AD) forest. DCDiag is a very good general-purpose testing tool for checking the health of the AD infrastructure. The available tests include replication errors, domain controller connectivity, permissions, proper roles, and connectivity, and other general AD health tests. DCDiag is even capable of running nondomain controller-specific tests like whether a server may be promoted to a domain controller (this is the dcpromo test). It can also register its records properly in DNS using the RegisterInDNS test.
DCDiag is run exclusively on domain controllers, with the only exceptions being the dcpromo and RegisterInDNS tests. When DCDiag is run without any parameters, all the tests are run against the current domain controller, this will run all the main tests and is normally sufficient for most purposes.
Accepted parameters for DCDiag are as follows :
When you are specifying tests to run or to skip, note that all nonskippable tests will be run regardless.
DCDiag is automatically included on Windows Server 2008 when the AD DS (Active Directory Domain Services) role is added. Alternatively, on non-domain controllers, the utility may be installed by adding the Remote Server Administration Tools feature from the Server Manager.