A server on a network – standalone or member – can function in a number of roles. As the needs of your computing environment change, you may want to change the role of a server. By using the Server Manager and the Add Roles Wizard, you can install Active Directory Domain Servers to promote a member server to a domain controller, or you can install individual roles or combinations of various roles, such as DHCP, WINS, and DNS.
It is also relatively straightforward to demote a domain controller to a simple role server or remove any number of roles and features from a server.
Server Manager is the key configuration console you will use for installing server roles and features on your server. It can be configured to open automatically as soon as you log in to the
Windows console or desktop.
Types of roles
Let’s look at the various roles and features you can install on Windows Server 2008.
Active Directory Certificate Services (AD CS)
AD CS role services install on a number of operating systems, including Windows Server 2008, Windows Server 2003, and Windows 2000 Server. Naturally the fullest implementation of AD CS is only possible on Windows Server 2008. You can deploy AD CS as a single standalone certification authority (CA), or you can deploy multiple servers and configure them as root, policy, and certificate issuing authorities. You also have a variety of Online Responder configuration possibilities.
Active Directory Domain Services (AD DS)
This is the role in the Windows Server 2008 operating system that stores information about users, computers, and other resources on a network. AD DS is also used for directory-enabled applications such as Microsoft Exchange Server.
Active Directory Federation Services (AD FS)
AD FS employs technology that allows users over the life of a single online session to securely share digital identity and entitlement rights, or ‘”claims” across security and enterprise boundaries. This role – introduced and supported on all operating systems since Microsoft Windows Server 2003 R2 – provides Web Single Sign-On (SSO) services to allow a user to access
multiple, related Web applications.
Active Directory Lightweight Directory Services (AD LDS)
This service is ideal if you are required to support directory-enabled applications. AD LDS is a Lightweight Directory Access Protocol (LDAP) compliant directory service.
Active Directory Rights Management Services (AD RMS)
This service augments an organization’s security strategy by protecting information through persistent usage policies. The key to the service is that the right management policies are bound to the information no matter where it resides or to where it is moved. AD RMS is used to lock down documents, spreadsheets, e-mail, and so on from being infiltrated or ending up in the wrong hands. AD RMS, for example, prevents e-mails from being accidentally forwarded to the wrong people.
The Application Server role
This role supports the deployment and operation of custom business applications that are built with Microsoft .NET Framework. The Application Server role lets you choose services for applications that require COM+, Message Queuing, Web services, and Distributed Coordinated Transactions.
DHCP and DNS
These two roles install these two critical network service services required for every network. They support Active Directory integration and support IPv6. WINS is not classified as a key role for Windows Server 2008, and you install it as a feature, discussed later.
Fax Server role
The fax server lets you set up a service to send and receive faxes over your network. The role creates a fax server and installs the Fax Service Manager and the Fax service on the server.
File Server role
This role lets you set up all the bits, bells, and whistles that come with a Windows file server. This role also lets you install Share and Storage Management, the Distributed File System (DFS), the File Server Resource Manager application for managing file servers, Services for Network File System (NFS), Windows File Services, which include stuff like the File Replication Service (FRS), and so on.
Network Policy and Access Services
This provides the following network connectivity solutions: Network Access Protection (NAP), the client health policy creation, enforcement, and remediation technology; secure wireless and wired access (802.1X), wireless access points, remote access solutions, virtual private network (VPN) services, Radius, and more.
Print Management role
The print services provide a single interface that you use to manage multiple printers and print servers on your network.
Terminal Services role
This service provides technologies that enable users to access Windows-based programs that are installed on a terminal server. Users can execute applications remotely (they still run on the remote server) or they can access the full Windows desktop on the target server.
Universal Description, Discovery, and Integration (UDDI)
UDDI Services provide capabilities for sharing information about Web services. UDDI is used on the intranet, between entities participating on an extranet, or on the Internet.
Web Server role
This role provides IIS 7.0, the Web server, ASP.NET, and the Windows Communication Foundation (WCF).
Windows Deployment Services
These services are used for deployment of new computers in medium to large organizations.
Features
Server Manager also lets you install dozens of features on Windows Server 2008. These so-called features are actually programs or supporting layers that support or augment the functionality of one or more roles, or simply add to the functionality of the server. A good example of a feature is the clustering service. Now called Failover Clustering, this feature can be used to support mission-critical roles such as File Services, Printer Services, and DHCP Server, on server clusters. This provides for higher availability and performance.
Other features you will likely install include SMTP Server, Telnet Client and Server, Group Policy Management (for use with Active Directory), Remote Assistance, and more.
Windows Management and Scripting 