1. What is Active Directory? Why do we need Active Directory? Active Directory stores all information and settings for a deployment in a central database. Active Directory allows administrators to assign policies, deploy and update software. Active Directory networks can vary from a small installation with a few computers, users and printers to tens of thousands of users, many different network domains and large server farms spanning many geographical locations. 2. What is Group Policy? What types of group policies are available? How does group policy apply on computers? Group Policy is a feature of the Microsoft Windows NT family of operating systems. Group Policy is a set of rules which control the working environment of user accounts and computer accounts. Group Policy provides the centralized management and configuration of operating systems, applications and users' settings in an Active Directory environment. In other words, Group Policy in part controls what users can and cannot do on a computer system. Although Group Policy is more often seen in use for enterprise environments, it is also common in schools, smaller businesses and other kinds of smaller organizations. Group Policy is often used to restrict certain actions that may pose potential security risks, for example: to block access to the Task Manager, restrict access to certain folders, disable the downloading of executable files and so on. You can have many different types of Group Policy ‘‘collections.’’ (The term policy collection is not a Microsoft term as far as we know, but it is useful for describing the policy types.) The following list describes the ‘‘intent’’ of these collections: 1) Application deployment: These policies are used to administer user access to applications. Application deployment or installation is controlled or managed in the following ways: a) Assignment: GP installs or upgrades applications and software on the client computers. The assignment can also be used to publish an icon or shortcut to an application and to ensure that the user cannot delete the icon. b) Application publication: Applications can be published in Active Directory. These applications are then advertised in the list of components that appears whenever a user clicks the Add/Remove icon in the Control Panel. 2) File deployment: These policies allow you to place files in certain folders on your user’s computer. For example, you can take aim at the user’s My Documents folder and provide the user with files that user needs to complete a project. 3) Scripting: These policies allow you to select scripts to run at predetermined times. They are especially useful for ensuring that scripts are processed during startup and shutdown or whenever a user logs off a machine and a new user logs on to the same machine. Windows Server 2008 can process VB scripts, JScripts, and scripts written to the Windows scripting host. 4) Software: These policies allow you to configure software on user workstations on a global or targeted scale. This is achieved by configuring settings in user profiles, such as the desktop settings, Start menu structure, and the other application menus. 5) Security: Perhaps no other collection in Windows Server 2008 is as important as the security policies, given that the next hacker who wipes out the assets could be the kid next door.
9. What’s the difference between forward lookup and reverse lookup in DNS? Forward lookup is name-to-address; the reverse lookup is address-to-name. 10. What is PING utility? Ping is a computer network administration utility used to test the reachability of a host on an Internet Protocol (IP) network and to measure the round-trip time for messages sent from the originating host to a destination computer. 11. What are major types of networks and explain? LAN - Local Area Network WLAN - Wireless Local Area Network WAN - Wide Area Network MAN - Metropolitan Area Network
12. What is RAID? Why it’s required? RAID, acronym for Redundant Array of Independent Disks (originally Redundant Array of Inexpensive Disks), is a technology that provides increased storage functions and reliability through redundancy.
13. What is a VLAN? What does VLAN provide? virtual local area network, virtual LAN or VLAN, is a group of hosts with a common set of requirements that communicate as if they were attached to the same broadcast domain, regardless of their physical location. A VLAN has the same attributes as a physical local area network (LAN), but it allows for end stations to be grouped together even if they are not located on the same network switch. LAN membership can be configured through software instead of physically relocating devices or connections.
14. Why should we care about the OSI Reference Model? What is the main purpose for creating this OSI model? Why it is a layered model? The Open Systems Interconnection model (OSI model) It is a way of sub-dividing a communications system into smaller parts called layers. Similar communication functions are grouped into logical layers. A layer provides services to its upper layer while receiving services from the layer below. On each layer, an instance provides service to the instances at the layer above and requests service from the layer below. For example, a layer that provides error-free communications across a network provides the path needed by applications above it, while it calls the next lower layer to send and receive packets that make up the contents of that path. Two instances at one layer are connected by a horizontal connection on that layer.
15. What is Router? A router is a device that forwards data packets between telecommunications networks, creating an overlay internetwork. A router is connected to two or more data lines from different networks. When data comes in on one of the lines, the router reads the address information in the packet to determine its ultimate destination. Then, using information in its routing table or routing policy, it directs the packet to the next network on its journey or drops the packet. A data packet is typically forwarded from one router to another through networks that constitute the internetwork until it gets to its destination node.
16. What is MAC address?
A Media Access Control address (MAC address) is a unique identifier assigned to network interfaces for communications on the physical network segment. MAC addresses are used for numerous network technologies and most IEEE 802 network technologies including Ethernet. Logically, MAC addresses are used in the Media Access Control protocol sub-layer of the OSI reference model. 17. What is the difference between *.ost and *.pst ? .ost (offline Folder) is a shadow copy of user Mailbox of Exchange server, starts as a mirror image of your folders on the Exchange Server in outlook and works in conjunction/Online with the Exchange Server during synchronization. .pst (Personal Folder) is simply a file containing Mails which is located on your local Hard disk. 18. What advance boot options are available for Windows XP? Safe mode Safe mode with networking Safe mode with command prompt Last known good configuration Normal mode 19. What is an IP address? Every device connected to the public Internet is assigned a unique number known as an Internet Protocol (IP) address. IP addresses consist of four numbers separated by periods (also called a 'dotted-quad') and look something like 127.0.0.1. 20. How do I clear the DNS cache on the DNS server? To clear DNS Cache do the following: 1. Start 2. Run 3. Type "cmd" and press enter 4. In the command window type "ipconfig /flushdns" 21. What is VPN? a virtual private network as the extension of a private network that encompasses links across shared or public networks like the Internet. With a VPN, you can send data between two computers across a shared or public network in a manner that emulates a point-to-point private link
22. What is LDAP? LDAP (Lightweight Directory Access Protocol) is a protocol for communications between LDAP servers and LDAP clients. LDAP servers store "directories" which are access by LDAP clients.
23. What are Organizational Units (OUs) Organizational units (OUs) can be considered logical units that can be used to organize objects into logical groups. OUs can be hierarchically arranged within a domain. An organization unit can contain objects such as user accounts, groups, computers, shared resources, and other OUs. You can also assign permissions to OUs to delegate administrative control. Domains can have their own OU hierarchy. Organizational units are depicted as folders in the Active Directory Users And Computers administrative tool. 24. What is the Global Catalog? The global catalog is a distributed data repository that contains a searchable, partial representation of every object in every domain in a multidomain Active Directory forest. The global catalog is stored on domain controllers that have been designated as global catalog servers and is distributed through multimaster replication. Searches that are directed to the global catalog are faster because they do not involve referrals to different domain controllers.