Determining the Directory Base DN

When you configure directory properties, you need to specify the common base Distinguished Name (DN) for users and groups. The base is defined in your directory server and differs from network to network. You must enter the correct bases for identity policies to work. If the base is wrong, the system cannot determine user or group names, and thus identity-based policies will be inoperable.

Note

To get the correct bases, consult the administrator who is responsible for the directory servers.

For an active directory, you can determine the correct bases by logging into the AD server as a domain administrator, and using the dsquery command at a command prompt as follows to determine the bases:

User search base

Enter the dsquery user command with known username (partial or complete) to determine the base distinguished name. For example, the following command uses the partial name "John*" to return information for all users that start with "John."

C:\Users\Administrator>dsquery user -name "John*"

"CN=John Doe,CN=Users,DC=csc-lab,DC=example,DC=com"

The base DN would be "DC=csc-lab,DC=example,DC=com."

Group search base

Enter the dsquery group command with a known group name to determine the base DN. For example, the following command uses the group name Employees to return the distinguished name:

C:\>dsquery group -name "Employees"

"CN=Employees,CN=Users,DC=csc-lab,DC=example,DC=com"

The group base DN would be "DC=csc-lab,DC=example,DC=com."

You can also use the ADSI Edit program to browse the AD structure (Start > Run > adsiedit.msc). In ADSI Edit, right click any object, such as an organizational unit (OU), group, or user, and choose Properties to view the distinguished name. You can then copy the string of DC values as the base.

To verify that you have the correct base:

Procedure


Step 1

Click the Test Connection button in the directory properties to verify connectivity. Resolve any problems, and save the directory properties.

Step 2

Commit changes to the device.

Step 3

Create an access rule, select the Users tab, and try to add known user and group names from the directory. You should see auto-complete suggestions as you type for matching users and groups in the realm that contains the directory. If these suggestions appear in a drop-down list, then the system was able to query the directory successfully. If you see no suggestions, and you are certain the string you typed should appear in a user or group name, you need to correct the corresponding search base.


What to do next

See Create and Edit a Firepower Threat Defense Active Directory Realm Object for more information.