Installing and Configuring the CA Cluster

Applies To: Windows Server 2008

The following sections describe the installation and configuration of a certification authority (CA) on a failover cluster running on Windows Server® 2008.

  • Define a naming convention to use in the cluster configuration.

  • Set up the CA role service on the first cluster node.

  • Set up the CA role service on the second cluster node.

  • Set up the failover cluster feature on both cluster nodes.

  • Create the failover cluster.

  • Configure the failover cluster.

  • Configure the certificate revocation list (CRL) distribution point.

  • Create the CRL distribution point container in Active Directory® Domain Services (AD DS).

  • Configure the CA in AD DS.

  • Adjust the CA names in AD DS.

Defining a naming convention to use in the cluster configuration

Before you begin, you should plan the names to use during the installation procedure. It is important to properly define these names because they are used throughout the configuration.

The following named items are used in the subsequent sections and step-by-step procedures.

Item Description Configuration Uses

Cluster node

Every computer running Windows has a name; therefore, computers acting as cluster nodes have a computer name.

The computer name is configured in the properties of a Windows–based computer.

The computer names of the nodes are permitted on access control lists (ACLs) in the following Active Directory objects in the configuration naming context under Services\Public Key Services:

  • Authority Information Access (AIA) – CA name

  • Enrollment Services – CA name

  • Enrollment Services – KRA

Cluster

The failover cluster has a unique name that is registered in AD DS.

The cluster name is configured when the failover cluster is set up. See step 8 in Setting up failover clustering.

The name of the cluster is used to refer to a specific cluster in the Failover Cluster Management snap-in. There is no dependency between this name and the CA.

Service

The service name represents the Domain Name System (DNS) name of the clustered CA service.

The service name is configured when the CA is set up as a clustered service. See step 5 in Configuring AD CS as a cluster resource.

The service name appears as part of the CA configuration string. The service name is represented in the following Active Directory object in the configuration naming context under Services\Public Key Services: Certificate Revocation List (CRL) Distribution Point (CDP) – Service name.

You can obtain the service name by opening a command prompt window and running the following command: certutil -cainfo dns.

CA

The CA is the actual name of the CA.

The name of the CA is configured when the CA service is installed. See step 12 in Setting up the CA role service on the first cluster node.

The CA name is part of the CA configuration string and is displayed as the node name in the Certification Authority snap-in. The name is written into the Issuer attribute on every issued certificate and is also used in the following Active Directory objects in the configuration naming context under Services\Public Key Services:

  • AIA – CA name

  • CDP – Service nameCA name

  • Certification Authorities – CA name

  • Enrollment Services – CA name

  • Key Recovery Agent (KRA) – CA name

You can obtain the CA name by opening a command prompt window and running the following command: certutil -cainfo name.

Setting up the CA role service on the first cluster node

This section explains how to install AD CS on the first cluster node.

The configuration of the first cluster node includes the following tasks:

  • Confirm that the shared disk is available to the node.

Note

The shared resources, such as the disk storage containing the CA database and log file, must be available to the CA during setup. Releasing these resources for setting up the second node is also important after the setup of this node is finished.

  • Confirm that the network hardware security module (HSM) is available to the node.

  • Install the CA on the first node.

  • Export the CA certificate (and, optionally, the private key) to share it with the second node.

  • Shut down the CA service on the first node.

  • Take the shared storage offline.

  • Release the HSM from the first node.

To configure the first cluster node

  1. Log on to the first server with permissions to install the first cluster node. To install an enterprise CA, you need to be a member of the Enterprise Admins group for the Active Directory domain. To install a stand-alone CA, you can log on as a member of the local Administrators group, but you will not be able to register the CA in the Active Directory configuration container.

  2. Click Start, and then click Server Manager.

  3. In the console tree, double-click Storage, and then click Disk Management. Confirm that the shared disk that is used for the CA is online.

  4. In the console tree, double-click Diagnostics, and then click Services. If you are using a network HSM, confirm that the service that connects to the network HSM is running.

  5. In the console tree, click Roles. On the Action menu, click Add Roles.

  6. On the Select Server Roles page, click Active Directory Certificate Services, and then click Next twice.

  7. On the Select Role Services page, select the Certification Authority role service, and then click Next. Do not select any other role services. Only the CA role service is supported in a clustered environment.

  8. Select the setup type for the CA, and click Next.

  9. Select the CA type for the CA, and click Next.

  10. Select Create a new private key, and click Next.

  11. If you are using a network HSM, select the cryptographic service provider (CSP) provided by the HSM vendor from the list and set the desired key length. Click Next.

  12. Enter the CA name, and click Next. For more information about the CA name, see Defining a naming convention to use in the cluster configuration.

  13. If you are configuring a root CA, define the validity period. If you are using a subordinate CA, choose whether to submit the request online or save it to a file. Click Next.

  14. Change the default paths for the database and log files to the desired location on the shared storage drive that you set up in Preparing the CA Cluster Environment. Click Next, and then click Install.

  15. After the CA installation is complete, open the Certification Authority snap-in. In the console tree, select the CA node. On the Action menu, click All Tasks, and then click Backup CA.

  16. On the Welcome page of the CA Backup Wizard, click Next. Select Private key and CA certificate, and provide a directory name where you want to temporarily store the CA certificate and optionally the key. Click Next.

  17. Provide a password to protect the CA key, click Next, and then click Finish.

  18. If you are using a network HSM, a warning message will display telling you that the private key cannot be exported. This is expected behavior because the private key will never leave the HSM. Click OK.

  19. While the CA is selected in the console tree, on the Action menu, click All Tasks, and then click Stop Service.

  20. Detach the shared storage from the cluster node. In the Server Manager console tree, double-click Storage, and then click Disk Management. Change the state of the disk containing the CA database to offline. Then, release the HSM from the cluster node.

  21. In the console tree, double-click Diagnostics, and click Services. If you are using a network HSM, select the service that works with the HSM. On the Action menu, click Stop. Log off from the first cluster node.

The installation of the CA on the first node is now complete.

Setting up the CA role service on the second node

This section explains how to set up the second cluster node. The configuration of the second node is slightly different from the first node. Some configuration settings are already defined on the first node so they only need to be applied on the second node.

The configuration of the second node includes the following tasks:

  • Confirm that the shared disk is available to the node.

  • Confirm that the network HSM is available to the node.

  • Import the CA certificate into the local computer certificate store.

  • Associate the CA certificate with the key material stored in an HSM (this step is optional).

  • Install AD CS on the second node.

The following procedure describes these tasks in greater detail.

To set up the CA role service on the second node

  1. Log on to the cluster node with the same permissions used to install the first cluster node. To install an enterprise CA, log on as a member of the Enterprise Admins group to the Active Directory domain. To install a stand-alone CA, you can log on as a member of the local Administrators group, but you will not be able to register the CA in the Active Directory configuration container.

  2. Open Server Manager. In the console tree, double-click Storage, and click Disk Management. Verify that the shared disk that is used for the CA is online.

  3. In the console tree, double-click Diagnostics, and click Services. If you are using a network HSM, confirm that the service that connects to the network HSM has started.

  4. Open the Certificates snap-in for the computer account.

  5. In the console tree, double-click Certificates (Local Computer), and click Personal.

  6. On the Action menu, click All Tasks, and then click Import to open the Certificate Import Wizard. Click Next.

  7. Enter the file name of the CA certificate that was previously created on the first node, and click Next. If you click Browse to find the certificate, change the file type to Personal Information Exchange (*.pfx,*.p12).

  8. Type the password that you have previously used to protect the private key. The password is required even if there is no private key in the .pfx file. Do not mark this key as exportable. Click Next.

  9. Place the certificate in the Personal certificate store, and click Next. To complete the certificate import process, click Finish, and then click OK.

  10. If you are using a network HSM, you must repair the association between the certificate and the private key that is stored in the HSM. In the Certificates snap-in, double-click Personal Certificates, and select the certificate that you just imported.

  11. On the Action menu, click Open. Click the Details tab, copy the serial number to the Clipboard, and then click OK.

  12. Open a command prompt window, type certutil –repairstore My "{Serialnumber}" and then press ENTER.

  13. Open Server Manager, select the Roles node, and on the Action menu, click Add Roles.

  14. On the Select Server Roles page, select Active Directory Certificate Services, and click Next twice.

  15. On the Select Role Services page, select Certification Authority, and click Next. The CA role service is the only AD CS role service that can be configured to use clustering.

  16. Select the same setup type for the CA that you used for the first node, and click Next.

  17. Select the same CA type for the CA that you used for the first node, and click Next.

  18. Select Use existing private key, select Select a certificate and use its associated private key, then click Next.

  19. Select the CA certificate that was generated on the first node, and click Next.

  20. Change the default paths for the database. In the dialog box stating that an existing database was found, select Yes to overwrite it. Click Next to continue.

  21. Click Install. To finish the role installation, click Close. Log off from the second cluster node.

Setting up failover clustering

Failover clustering support is a feature in Windows Server 2008 Enterprise. The following steps must be completed on both cluster nodes.

To set up failover clustering on a server

  1. Log on to the cluster node as a member of the local Administrators group.

  2. Open Server Manager. In the console tree, click Features, and on the Action menu, click Add Features.

  3. In the list of available features, select Failover Clustering, and click Next. Click Install, and then click Close.

  4. Log on to the second cluster node (the storage should still be attached to that node). Click Start, point to Run, type Cluadmin.msc, and then click OK.

  5. If the Before you begin page appears, click Next. Enter the cluster node name (computer name) of the first cluster node, and click Add.

  6. Enter the name of the second cluster node, click Add, and then click Next to continue.

  7. To test the cluster, click Yes, and click Next twice. Keep the default option to Run all tests, and click Next twice. Verify the cluster test report, and click Finish.

  8. Provide the cluster name. This name is not relevant for the later CA configuration. View the cluster setup information page, and click Finish.

Configuring AD CS as a cluster resource

Before closing the Failover Cluster Management snap-in, configure AD CS as a cluster resource.

To configure AD CS as a cluster resource

  1. In the console tree of the Failover Cluster Management snap-in, click Services and Applications.

  2. On the Action menu, click Configure a service or Application. If the Before you begin page appears, click Next.

  3. In the list of services and applications, select Generic Service, and click Next.

  4. In the list of services, select Active Directory Certificate Services, and click Next.

  5. Choose the service name, and click Next. For more information about the service name, see Defining a naming convention to use in the cluster configuration.

  6. Select the disk storage that is still mounted to the node, and click Next.

  7. To configure a shared registry hive, click Add, type SYSTEM\CurrentControlSet\Services\CertSvc, and then click OK. Click Next twice.

  8. Click Finish to complete the failover configuration for AD CS.

  9. In the console tree, double-click Services and Applications, and select the newly created clustered service.

  10. In the details pane, click Generic Service. On the Action menu, click Properties.

  11. Change the Resource Name to Certification Authority, and click OK.

You can now move the CA between both nodes.

If you have installed a service to access the network HSM, you should create a dependency between the CA and the network HSM service.

To create a dependency between a CA and the network HSM service

  1. Open the Failover Cluster Management snap-in. In the console tree, click Services and Applications. In the details pane, select the previously created name of the clustered service. On the Action menu, click Add a resource, and then click Generic Service.

  2. The new resource wizard appears. In the list of available services, select the name of the service that was installed to connect to your network HSM. Click Next twice, and then click Finish.

  3. Under Services and Applications in the console tree, click the name of the clustered services.

  4. In the details pane, select the newly created Generic Service. On the Action menu, click Properties.

  5. On the General tab, rename the service name if desired, and click OK. Confirm that the service is online.

  6. In the details pane, select the service previously named Certification Authority. On the Action menu, click Properties.

  7. On the Dependencies tab, click Insert, select the network HSM service from the list, and then click OK.

Configuring the CRL distribution point

In the default CA configuration, the server's short name is used as part of the CRL and authority information access path. When a CA is running on a failover cluster, the server's short name must be replaced with the cluster's short name in the CRL and authority information access URL. To publish the CRL in AD DS, the CRL distribution point container must be added manually.

Note

All CA configuration tasks should be performed on the active cluster node. You must restart the CA service after changing the CRL and authority information access.

To change the configured CRL distribution points

  1. Log on to the active cluster node as a member of the local Administrators group.

  2. Click Start, point to Run, type regedit, and then click OK.

  3. Expand the following containers in the registry: HKLM\SYSTEM\CurrentControlSet\Services\CertSvc\Configuration.

  4. Select the name of the CA in the Configuration container.

  5. In the right pane, open CRLPublicationURLs to edit this entry.

  6. In the second line, replace %2 with the service name that was defined in step 5 of Configuring AD CS as a cluster resource. The service name also appears in the Failover Cluster Management snap-in under Services and Applications.

  7. After the new path is entered, set all publishing options to be the same as the default LDAP URL; either completely remove the default entry or remove all the publish options.

  8. Open a command prompt window, type net stop certsvc && net start certsvc, and press ENTER to restart the CA service.

  9. At the command prompt, type certutil -CRL, and press ENTER to update the CRL with the new settings applied previously.

Note

If you receive an error stating "Directory object not found," complete the following procedure to create the CRL distribution point container in AD DS.

To create the CRL distribution point container in AD DS

  1. At the command prompt, type cd %windir%\System32\CertSrv\CertEnroll, and press ENTER. The CRL file created by the certutil –CRL command should be located in this directory.

  2. To publish the CRL in AD DS, type certutil -f -dspublish "CRLFile.crl", and press ENTER.

Configuring the CA in AD DS

You need to complete three procedures to configure the CA in AD DS:

  • Enable both cluster nodes to update the CA certificate when required.

  • Give both nodes permissions on the Enrollment container.

  • Give both nodes permissions on the KRA container.

To enable both cluster nodes to update the CA certificate when required

  1. Log on to the computer as a member of the Enterprise Admins group, and open the Active Directory Sites and Services snap-in.

  2. In the console tree, select the top node. On the View menu, click Show services node.

  3. In the console tree, double-click Services, double-click Public Key Services, and then click AIA.

  4. In the details pane, select the CA name as it appears in the Certification Authority snap-in.

  5. On the Action menu, click Properties. Click the Security tab, and then click Add.

  6. Click Object Types, select Computers, and then click OK.

  7. Type the computer name of the second cluster node as the object name, and click OK.

  8. Confirm that the computer accounts of both cluster nodes have Full Control permissions, and then click OK.

To give both nodes permissions on the Enrollment container

  1. Log on to the computer as a member of the Enterprise Admins group, and open the Active Directory Sites and Services snap-in.

  2. In the console tree, select the top node. On the View menu, click Show services node.

  3. In the console tree, double-click Services, double-click Public Key Services, and then click AIA.

  4. In the console tree, click Enrollment Services. In the details pane, select the CA name.

  5. On the Action menu, click Properties. Click the Security tab, and then click Add.

  6. Click Object Types, select Computers, and click OK.

  7. Type the computer name of the second cluster node as the object name, and click OK.

  8. Confirm that the computer accounts of both cluster nodes have Full Control permissions, and then click OK.

To give both nodes permissions on the KRA container

  1. Log on to the computer as a member of the Enterprise Admins group, and open the Active Directory Sites and Services snap-in.

  2. In the console tree, select the top node. On the View menu, click Show services node.

  3. In the console tree, double-click Services, double-click Public Key Services, and then click KRA.

  4. In the details pane, select the CA name.

  5. On the Action menu, click Properties. Click the Security tab, and then click Add.

  6. Click Object Types, select Computers, and then click OK.

  7. Type the computer name of the second cluster node as object name, and click OK.

  8. Confirm that the computer accounts of both cluster nodes have Full Control permissions, and then click OK.

Adjusting the DNS name for the CA in AD DS

When the CA service was installed on the first cluster node, it created the Enrollment Services object and put its own fully qualified domain name (FQDN) into that object. Since the CA can operate on both cluster nodes, the DNS host name of the Enrollment Services object needs to be changed to the service name of the CA.

To adjust the DNS name for the CA in AD DS

  1. Log on to the computer as a member of the Enterprise Admins group, and open the ADSI Edit snap-in.

  2. In the console tree, click ADSI Edit. On the Action menu, click Connect to.

  3. In the list of well-known naming contexts, select Configuration, and click OK.

  4. In the console tree, double-click Configuration, Services, and Public Key Services, and then click Enrollment Services.

  5. In the details pane, select the name of the cluster CA. On the Action menu, click Properties.

  6. Select the attribute dNSHostName, and click Edit.

  7. Enter the service name of the CA as shown in the Failover Cluster Manager under Failover Cluster Management, and click OK twice. Close ADSI Edit.