32.What does the physical structure of active directory contain?

What does the physical structure of active directory contain?

Physical structures include domain controllers and sites.

31.What does the logical component of the Active Directory structure include?

What does the logical component of the Active Directory structure include?

 

Objects:-Resources are stored in the Active Directory as objects.

Sub category: object class

An object is really just a collection of attributes. A user object, for example, is made up of attributes such as name, password, phone number, group membership, and so on. The attributes that make up an object are defined by an object class. The user class, for example, specifies the attributes that make up the user object.

The Active Directory Schema:-

The classes and the attributes that they define are collectively referred to as the Active Directory Schema—in database terms, a schema is the structure of the tables and fields and how they are related to one another. You can think of the Active Directory Schema as a collection of data (object classes) that defines how the real data of the directory (the attributes of an object) is organized and stored

■ Domains

The basic organizational structure of the Windows Server 2003 networking model is the domain. A domain represents an administrative boundary. The computers, users, and other objects within a domain share a common security database.

■ Trees

Multiple domains are organized into a hierarchical structure called a tree. Actually, even if you have only one domain in your organization, you still have a tree. The first domain you create in a tree is called the root domain. The next domain that you add becomes a child domain of that root. This expandability of domains makes it possible to have many domains in a tree. Figure 1-1 shows an example of a tree. Microsoft.com was the first domain created in Active Directory in this example and is therefore the root domain.

 

Figure 1-1 A tree is a hierarchical organization of multiple domains.

All domains in a tree share a common schema and a contiguous namespace. In the example shown in Figure 1-1, all of the domains in the tree under the microsoft.com root domain share the namespace microsoft.com. Using a single tree is fine if your organization is confined within a single DNS namespace. However, for organizations that use multiple DNS namespaces, your model must be able to expand outside the boundaries of a single tree. This is where the forest comes in.

 

■ Forest

A forest is a group of one or more domain trees that do not form a contiguous namespace but may share a common schema and global catalog. There is always at least one forest on a network, and it is created when the first Active Directory–enabled computer (domain controller) on a network is installed.

This first domain in a forest, called the forest root domain, is special because it holds the schema and controls domain naming for the entire forest. It cannot be removed from the forest without removing the entire forest itself. Also, no other domain can ever be created above the forest root domain in the forest domain hierarchy.

Figure 1-2 shows an example of a forest with two trees. Each tree in the forest has its own namespace. In the figure, microsoft.com is one tree and contoso.com is a second tree. Both are in a forest named microsoft.com (after the first domain created)

 

Figure 1-2 Trees in a forest share the same schema, but not the same namespace.

A forest is the outermost boundary of Active Directory; the directory cannot be larger than the forest. However, you can create multiple forests and then create trust relationships between specific domains in those forests; this would let you grant access to resources and accounts that are outside of a particular forest.

 

■Organizational Units

Organizational Units (OUs) provide a way to create administrative boundaries within a domain. Primarily, this allows you to delegate administrative tasks within the domain.

OUs serve as containers into which the resources of a domain can be placed. You can then assign administrative permissions on the OU itself. Typically, the structure of OUs follows an organization’s business or functional structure. For example, a relatively small organization with a single domain might create separate OUs for departments within the organization.

30. DNS Records

DNS Records

After you create a zone, additional resource records need to be added to it. The most common resource records (RRs) to be added are:

Table 5. Record Types

Name	Description
Host (A)	For mapping a DNS domain name to an IP address used by a computer.
Alias (CNAME)	For mapping an alias DNS domain name to another primary or canonical name.
Mail Exchanger (MX)	For mapping a DNS domain, name to the name of a computer that exchanges or forwards mail.
Pointer (PTR)	For mapping a reverse DNS domain name based on the IP address of a computer that points to the forward DNS domain name of that computer.
Service location (SRV)	For mapping a DNS domain name to a specified list of DNS host computers that offer a specific type of service, such as Active Directory domain controllers.
	Other resource records as needed.

29. Types of DNS Zones

Types of DNS Zones.

Ans : There are two types of zones, forward lookup and reverse lookup. 

Forward lookup zones contain information needed to resolve names within the DNS domain. They must include SOA and NS records and can include any type of resource record except the PTR resource record. 

Reverse lookup zones contain information needed to perform reverse lookups. They usually include SOA, NS, PTR, and CNAME records.

With most queries, the client supplies a name and requests the IP address that corresponds to that name. This type of query is typically described as a forward lookup. Active Directory requires forward lookup zones.

However, what if a client already has a computer's IP address and wants to determine the DNS name for the computer? This is important for programs that implement security based on the connecting FQDN, and is used for TCP/IP network troubleshooting. The DNS standard provides for this possibility through reverse lookups.

Once you have installed Active Directory, you have two options for storing your zones when operating the DNS server at the new domain controller:

Standard Zone

Zones stored this way are located in .dns text files that are stored in the %SystemRoot%\System32\Dns folder on each computer operating a DNS server. Zone file names correspond to the name you choose for the zone when creating it, such as Example.microsoft.com.dns if the zone name was example.microsoft.com.

This type offers the choice of using either a Standard Primary zone or a Standard Secondary zone.

Standard Primary Zone
For standard primary-type zones, only a single DNS server can host and load the master copy of the zone. If you create a zone and keep it as a standard primary zone, no additional primary servers for the zone are permitted. Only one server is allowed to accept dynamic updates, also known as DDNS, and process zone changes. The standard primary model implies a single point of failure.

Standard Secondary Zone
A secondary name server gets the data for its zones from another name server (either a primary name server or another secondary name server) for that zone across the network. The data in a Secondary zone is Read only, and updated information must come from additional zone transfers. The process of obtaining this zone information (i.e., the database file) across the network is referred to as a zone transfer. Zone transfers occur over TCP port 53.
 
Secondary servers can provide a means to offload DNS query traffic in areas of the network where a zone is heavily queried and used. Additionally, if a primary server is down, a secondary server can provide some name resolution in the zone until the primary server is available.

28. What Are DNS Zones?

What Are DNS Zones?

ANS : A zone starts as a storage database for a single DNS domain name. If other domains are added below the domain used to create the zone, these domains can either be part of the same zone or belong to another zone. Once a subdomain is added, it can then either be:

●    Managed and included as part of the original zone records, or
●    Delegated away to another zone created to support the subdomain