To verify that a server is advertised as a global catalog server, you can use the DNS Manager snap-in to verify the presence of Domain Name System (DNS) service location (SRV) resource records for the global catalog server.

Membership in the Enterprise Admins group in the forest or the Domain Admins group in the forest root domain, or equivalent, is the minimum required to complete these procedures. Review details about using the appropriate accounts and group memberships at

To verify global catalog DNS registrations
  1. Restart the global catalog server whose DNS registrations you want to verify.

  2. Open DNS Manager. To open DNS Manager, click Start, click Administrative Tools, and then click DNS.

  3. To connect to a domain controller in the forest root domain for which you want to verify DNS registrations, right-click DNS, and then click Connect to DNS Server.

  4. In the console tree, click the _tcp container for the forest root domain.


    • DNS\DNSServer\Forward Lookup Zones\ForestRootDomain\

  5. In the details pane, in the Name column, look for _gc, and in the Data column, look for the name of the server. The records that begin with _gc are global catalog service location (SRV) resource records.

Additional considerations

  • To perform this procedure, you must be a member of the Domain Admins group in the domain of the selected domain controller or the Enterprise Admins group in the forest, or you must have been delegated the appropriate authority. As a security best practice, use Run as administrator to perform this procedure. Log on with your lowest-level user account and use administrative credentials when you manage Active Directory Domain Services (AD DS).

Additional references