An RODC contains a read only copy of all the objects in the domain to allow local authentication of users in each branch office. It performs replication with the domain controller at the main site to keep its data updated. RODC also reduces the physical security threat for the domain controller at the branch office because it does not keep a copy of confidential attributes (secrets) such as password-related properties on it. In case the security is compromised, much harm is not caused.
Before installing the Read Only Domain Controller in your forest/domain, you need to:
Ensure that the Forest functional level of the domain/forest is Windows Server 2003 or higher. If the domain has any Windows Server 2003 domain controller running in it. Run adprep / rodcprep. This command prepares the domain controllers that are running Windows Server 2003 for replication of DNS application directory partitions.
Ensure that at least one writable domain controller is running Windows Server 2008 to ensure that the RODC is able to establish a connection with writable Windows Server 2008 to perform replication.
You can install RODC on a full installation or the core installation of Windows Server 2008 on a member server in the domain.
To install RODC on a full installation of Windows Server 2008, you need to:
Ensure that your Primary Domain Controller is switched on.
Log on to the Windows Server 2008 server that you want to configure as RODC with domain administrative credentials.
Click Start->Run and type dcpromo.A window informing you about the installation of Active Directory Domain Services binaries appears. After this installation is complete the Active Directory Domain Services Installation Wizard appears.
Click Next on the Operating System Compatibility page that appears.The Choose a Deployment Configuration page appears. The page allows you to create a new domain or a forest or add new domain controllers or new domains to the existing forest.
Select Existing forest option and then select Add a domain controller to an existing domain option under it and click Next, as shown in Figure 4-9.The RODC is always added to the existing forest in the existing domain.
The Network Credentials page appears, as shown in Figure 4-11.
The page allows you to provide the name of the forest/domain where you want to add the RODC.
Provide the name of the domain in which you want to add RODC in the Type the name of any domain in the forest where you want to plan to install this domain controller field.
Select Alternate credentials option and then click Set.
Provide your domain administrative credentials in the Username and the Password fields respectively and click OK on the Windows Security page that appears.The username that you have provided along with the domain name appears in the Alternate credentials field.
Click NextThe Examining Active Directory forest window appears. The window tries to establish a connection between the domain controller and this server with the account credentials that you had provided in the previous step so that RODC can be installed on this server.
Select the domain for this domain controller and click Next on the Select a Domain page that appears, as shown in Figure 4-12.
The Select a Site page appears.
Select the site that you created for the new branch office for which you want to install the RODC.If no site is created then the Default-First-Site-Name option appears, as shown in Figure 4-13.
The Additional Domain Controller Options page appears, as shown in Figure 4-14.
Select Read-only domain controller (RODC) option from the Select additional options from the domain controller field.
Verify that DNS Server and Global catalog options are also selected.
The Delegation of RODC Installation and Administration page appears, as shown in Figure 4-15.
The page allows you to specify the name of a user or group who will have local administrative rights on this RODC to attach servers to it.
Provide the user name or the group name in the Group or user field optionally and click Next.
The Location for Database, Log Files, and SYSVOL page appears.
Verify/modify the locations of Database folder, Log files folder, and SYSVOL folder in their respective fields and click Next.The Directory Services Restore Mode Administrator Password page appears. The page allows you to set a password that will be used when this domain controller will be started in the Directory Services Restore mode to restore the Directory services.
Provide a strong password in the Password field and retype the password in the Confirm password field.
Verify the selection you have made up till now to install RODC on this server and click Next on the Summary page appears.The Active Directory Domain Services Installation Wizard page appears displaying the progress of the installation.
Select Reboot on completion checkbox and click Finish.
Follow the steps given below to install and configure an Active Directory Domain Controller:
To Install AD DS on the server, you need to:
Log on to the server with local Administrator account.
Click Add roles under Customize This Server in the Server Manager window, if it opens automatically.Alternatively, you can click Start-> Settings->Control Panel-> Administrative Tools- >Server Manager and then right-click the Roles node and select Add Roles. The Add Roles Wizard appears.
Verify the requirements to add roles on the server and click Next. The Select Server Roles page appears.
Select Active Directory Domain Services option from the Roles field and click Next. The Active Directory Domain Services page appears. The page provides you all the information about AD DS that you may need to know before installing and using this service.
Click Next. The Confirm Installation Selection page appears.
Click Install. The Installation Progress page appears. After the installation is complete, the Installation Results page appears
Type dcpromo.exe in the Run dialog box. The Active Directory Domain Services installation Wizard appears.
Click Next. The Operating System Compatibility page appears. The page provides you information about Windows Server 2008 compatibility with older versions of Windows.
Click Next. The Choose a Deployment Configuration page appears.The page provides you options to use the existing forest and create a new domain or add a domain controller to it or create a new domain in a new forest.
Select Create a new domain in a new forest option and click Next, as shown in Figure 3-1.The first domain created in your forest becomes the forest root domain. You can keep this existing domain as a forest root domain or create a dedicated forest root domain in a multidomain scenario. If you have a single domain forest then the forest root domain will contain all the users, groups, and resources. However, if you have a multiple domain forest and you create a dedicated forest root domain, then it will contain only forest administration accounts.
Type the complete name of the forest that you are creating in the FQDN of the forest root domain field on the Name the Forest Root Domain page that appears, as shown in Figure 3-2.
Select the forest functional level as Windows Server 2008 from the Forest functional level dropdown on the Set Forest Functional Level page that appears, as shown in Figure 3-3.Each forest functional level supports certain features. Windows Server 2008 supports three forest functional levels. These functional levels are:
Windows 2000: Windows 2000 functional level is the baseline, default functional level that allows domains running at domain functional levels: Windows 2000 native, Windows Server 2003, or Windows Server 2008.
Windows Server 2003: This functional level allows a domain controller running Windows Server 2003 to interact with Windows Server 2003 or Windows Server 2008 domain controllers. The forest functional level should be Windows Server 2003 when there are only Windows 2003 or Windows 2008 domain controllers in the domain. This level supports forests trusts, domain rename, linked value replication, and RODC.
Windows Server 2008: This functional level does not add any new forest wide features. This forest level allows only Windows Server 2008 domain controllers to be added to the forest.
Select the appropriate forest functional level and then click Next.The forest functional level can be raised at a later stage also through Active Directory Domains and Trusts snap-in when the AD DS is installed. However, you should only raise the functional levels when you are sure that you will not need any new domains to be added at unsupported functional levels because you cannot roll back to the previous functional level.
The Additional Domain Controller Options page appears, as shown in Figure 3-4. The page allows you to select the additional roles for this domain controller. All the options: DNS Server, Global Catalogue, and RODC appear disabled. This is because the DNS server role is already installed on the server, the first domain controller in a forest must be a Global Catalog therefore it must be selected, and the first domain controller in a domain cannot become an RODC.
If you have not already assigned a static IP address, then a warning message appears.
Click the Yes, the computer will use a dynamically assigned IP address (Not Recommended option) option.
Another warning message appears that server cannot create a delegation for this server, as shown in Figure 3-5. Click Yes to continue with the installation because you can create the delegation later. You get this message at the time of installing the first domain controller in a forest/domain.
Accept the default locations for the Database folder, Log files folder, and SYSVOL folder on the Locations for Database, Log Files, and SYSVOL page that appears and click Next, as shown in Figure 3-6.
Type a strong password on the Directory Services Restore Mode Administrative Password page, confirm it, and then click Next.
Confirm your selections on the Summary page and click Next. The DNS installation starts.
Select Reboot the computer and wait for the computer to boot again.
You can add child domains or new domain trees to your forest root domain.
To create a child domain you need to:
Install Active Directory on a Windows Server 2003 by clicking Start->Run and the typing dcpromo in the Run dialog box that appears.
Select Add a Domain controller to an existing domain option in the Choose a Deployment Configuration page and click Next, as shown in Figure 3-7.
Type inscription.com in the Type the name of any domain in the forest where you plan to install this domain controller textbox in the Network Credentials page.
Select My current logged on credentials option and then click Next
Select inscription.com in the Select a Domain page and click Next.
Select Default-First-Site-Name in the Select A Site page and then click Next. The Additional Domain Controller Options page appears.
Follow the steps from 16-22 given in Install and Configure Active Directory Domain Controller section.
The child domain will be created under the specified parent domain.
Configure Domain Name System (DNS) for Active Directory