Configure Microsoft CA server to prepare for DigiCert MCARS installation
Follow these initial configuration steps to prepare your Microsoft CA server for installation of the DigiCert MCARS service required for integration with DigiCert® Trust Lifecycle Manager.
1. Create a group
If you don't already have one, create a group to use with Active Directory Certificate Services (AD CS). You will use this group to grant MCARS access to the Microsoft CA server and certificate templates.
To create a group on the Windows server:
Open Server Manager > Active Directory Users and Computers.
Right-click the Organizational Unit (OU) or folder where you want to create the group and select New > Group.
Assign the group a friendly name,
Globalgroup scope, and group typeSecurity.
Example: Adding a new group called DigiCert MSCA Integration Group.
2. Create a service user
Next, create a service user to run the DigiCert MCARS service and make it a member of the security group from step 1.
To create the service user and add it to the group:
Open Server Manager > Active Directory Users and Computers.
Right-click the Organizational Unit (OU) or folder where you want to create the service user and select New > User.
Configure the basic user properties. Make note of the username and password, so you can use them with the DigiCert MCARS service.
Under the Member Of tab of the user properties, select Add and add the user to the security group from step 1.
Example: Adding the service user named MCARS Service Acct to the group called DigiCert MSCA Integration Group.
3. Create certificate templates
Next, create Microsoft CA certificate templates that DigiCert® Trust Lifecycle Manager can use to enroll certificate against the Microsoft CA.
Create a separate template for each type of Microsoft CA certificate you want to enroll via Trust Lifecycle Manager. This can include a mix of User and Server certificates.
Use the default Microsoft CA templates as the basis for creating the certificate templates:
Open Server Manager > Certificate Authority.
Expand the CA, right-click on Certificate Templates and select Manage to access the Certificate Templates Console.
Example: Managing certificate templates.
Locate the appropriate default template to use in the righthand pane of the Certificate Templates Console, right-click on it, and select Duplicate template. For server certificates, use the Server default template. For user certificates, start with the User default template instead.
Configure the basic properties of the new certificate template:
General tab: Assign a friendly name to the new certificate template and set the validity and renewal periods for certificates issued from this template.
Compatibility tab: Set the compatibility options to the latest values to support the most current TLS certificate features.
Subject Name tab: Make sure the Supply in the request option is selected.
Other tabs: Configure per your business and cryptographic requirements.
When you're happy with your selections, select OK to save the new certificate template. You can always update the certificate template later by right-clicking it and selecting Properties.
Example: Configuring the general properties of a new certificate template in the Certificate Templates Console.
4. Configure certificate template permissions
Configure the Microsoft CA certificate templates you created in step 3 to add the security group from step 1, so the DigiCert MCARS service can access them.
To add a security group to a certificate template:
From the Microsoft CA Certificate Templates Console, right-click on the template and select Properties.
In the Security tab, select Add and add the security group from step 1.
Give this security group the below permissions and select OK to save.
Read: Allows DigiCert to read data from this Microsoft certificate template.Write: Allows DigiCert to manage certificates using this Microsoft certificate template.Enroll: Allows DigiCert to enroll new certificates using this Microsoft certificate template.
Example: Adding the security group called DigiCert MSCA Integration Group to the certificate template called Web Server (90 days) with the required permissions.
5. Configure CA server permissions
Finally, configure the permissions of the Microsoft CA server itself to add the security group from step 1, so the DigiCert MCARS service can carry out the required operations.
To add a security group to a Microsoft CA server:
Right-click on the CA and select Properties.
In the Security tab, select Add and add the security group from step 1.
Give this group the below permissions and select OK to save.
Issue and Manage Certificates: Allows DigiCert to enroll and revoke certificates against the Microsoft CA.Request Certificates: Allows DigiCert to discover and import certificates from the Microsoft CA.
Example: Adding the security group called DigiCert MSCA Integration Group to a local Microsoft CA server with the required permissions.
Optional: Allow first SAN to become CN in automated certificates
If you will use DigiCert agents to automate certificates from the Microsoft CA, you can allow the first SAN in automation requests to become the CN in the issued certificates. By default, the CN is left blank when there are only SANs in the request.
Use the Windows Server certutil command to update the Microsoft CA configuration to allow override of the CN in certificates, as follows:
certutil -setreg ca\CRLFlags +CRLF_ALLOW_REQUEST_ATTRIBUTE_SUBJECT
Restart the Microsoft CA service after making this command for changes to take effect.
What's next
With the Microsoft CA server configured, you are ready to install and configure the DigiCert MCARS service.