Overview of Active Directory Domain ServicesLesson 1

Chapter ObjectivesIdentify Active Directory functions and Benefits.Identify the major components that make up an Active Directory structure.Identify how DNS relates to Active Directory.Identify Forest and Domain Functional Levels.

Directory ServiceA network service that identifies all resources on a network and makes those resources accessible to users and applications.The most common directory service standards are:X.500Lightweight Directory Access Protocol (LDAP)

X.500Uses a hierarchical approach in which objects are organized in a similar way to the files and folders on a hard drive.

Lightweight Directory Access Protocol (LDAP)Industry standard.Slim-down version of X.500 modified to run over the TCP/IP network.

Active DirectoryA directory service that uses the tree concept for managing resources on a Windows network.Stores information about the network resources and services, such as user data, printer, servers, databases, groups, computers, and security policies.Identifies all resources on a network and makes them accessible to users and applications.

Active DirectoryUsed in:Windows 2000Windows Server 2003Windows Server 2008Subsequent versions of Active Directory have introduced new functionality and security features.

Active DirectoryWindows Server 2008 provides two directory services:Active Directory Domain Services (AD DS)Active Directory Lightweight Directory Services (AD LDS)

Active Directory Domain Services (AD DS)Provides the full-fledged directory service that is referred to as Active Directory in Windows Server 2008 and previous versions of Windows Server.

Active Director Lightweight Directory Services (AD LDS)Provides a lightweight, flexible directory platform that can be used by Active Directory developers without incurring the overhead of the full-fledged Active Directory DS directory service.

Domain Controller (DC)Server that stores the Active Directory database and authenticates users with the network during logon.Stores database information in a file called ntds.dit.Active Directory is a multimaster database.Information is automatically replicated between multiple domain controllers.

Active Directory Functions and BenefitsCentralized resource and security administration.Single logon for access to global resources.Fault tolerance and redundancy.Simplified resource location.

Centralizing Resources and Security AdministrationActive Directory provides a single point from which administrators can manage network resources and their associates security objects:MMC Consoles found in Administrator Tools:Active Directory Users and ComputersActive Directory Sites and ServicesActive Directory Domains and TrustsADSI Edit

Fault Tolerance and RedundancyActive Directory uses a multimaster domain controller design.Changes made on one domain controller are replicated to all other domain controllers in the environment.It is recommended to have two or more domain controllers for each domain.

Read-Only Domain Controller (RODC)Introduced with Windows Server 2008.A domain controller that contains a copy of the ntds.dit file that cannot be modified and that does not replicate its changes to other domain controllers with Active Directory.

Simplifying Resource LocationAllows file and print resources to be published within Active Directory.Examples include:Shared foldersPrinters

Active Directory ComponentsForests One or more domain trees, with each tree having its own unique name space.Domain trees One or more domains with contiguous name space.Domains A logical unit of computers and network resources that defines a security boundary.

Active Directory ComponentsSome of these common attributes are as follows:Unique nameGlobally unique identifier (GUID)Required object attributesOptional object attributes

Understanding the SchemaDefines the objects stored within Active Directory the properties (attributes) associated within each object.User has different properties, which has different properties than a group, which has different properties of a computer.

Active Directory Naming StandardExample:cn=JSmith, ou=sales, dc=lucernepublishing, dc=com

Domain Name System (DNS)Provides name resolution for a TPC/IP network.Active Directory requires DNS as the default name resolution method.Example Resource Records (RR):Host (A) Host name to IP.Pointer (PTR) IP to Host name.Service (SRV) Locator service for LDAP/Domain controllers services.

Functional LevelsAllows interoperability with prior versions of Microsoft Windows.Higher levels of functional level will not allow older versions of Windows to function but will add additional functionality or features.Raising functional level is a one-way process.

Domain Functional Levels

Forest Functional Levels

Using Forest Functional LevelsTo raise the functional level of a forest, you must be logged on as a member of the Enterprise Admins group.The functional level of a forest can be raised only on a server that holds the Schema Master role.

Trust RelationshipsActive Directory uses trust relationships to allow access between multiple domains and/or forests, either within a single forest or across multiple enterprise networks. A trust relationship allows administrators from a particular domain to grant access to their domains resources to users in other domains.

Trust RelationshipsWhen a child domain is created, it automatically receives a two-way transitive trust with its parent domain. Trusts are transitive:If domain A trusts domain BAnd domain B trusts CThen domain A trusts domain C

Chapter SummaryActive Directory is a database of objects that are used to organize resources according to a logical plan. These objects include containers such as domains and OUs in addition to resources such as users, computers, and printers.The Active Directory schema includes definitions of all objects and attributes within a single forest. Each forest maintains its own Active Directory schema.

Chapter SummaryActive Directory requires DNS to support SRV records. Microsoft recommends that DNS support dynamic updates.

Chapter SummaryDomain and forest functional levels are new features of Windows Server 2008. The levels defined for each of these are based on the type of server operating systems that are required by the Active Directory design. The Windows Server 2003 forest functional level is the highest functional level available and includes support for all Windows Server 2003 features.

Chapter SummaryTwo-way transitive trusts are automatically generated within the Active Directory domain structure.Parent and child domains form the trust path by which all domains in the forest can traverse to locate resources. The ISTG is responsible for this process.

Chapter SummaryCross-forest trusts are new to Windows Server 2003, and they are only available when the forest functionality is set to Windows Server 2003. They must be manually created and maintained.

*********This feature is new starting with Windows Server 2008.******Forest, domain trees and domains represent a logical representation.OUs can also be used to organize resources within a domain.Domain Controllers and sites are physical components.

***Essential to install DNSIf not available during installation, you can install DNS at the same time.*****In a nutshell, all domains trust other domains within a tree.*****