300+ TOP System Administration Interview Questions and Answers

Q1. What Is The Windows Registry?

The Windows Registry, usually referred to as “the registry,” is a collection of databases of configuration settings in Microsoft Windows operating systems.

Q2. When Do We Use Wds?

Windows Deployment Services is a server role used to deploy Windows operating systems remotely. WDS is mainly used for network-based OS installations to set up new computers.

Q3. Where Is The Ad Database Stored?

The AD database is stored in C:WindowsNTDSNTDS.DIT.

Q4. Differentiate Between Firewall/antivirus?

Antivirus: The prime job of an anivirus is protect your system from computer viruses. Your computer may be standalone or part of network or connected to Internet you need an antivirus program. It actively monitors when you are using your system for any virus threat from different sources. if it found one it tries to clean or quarantine the virus ultimately keeping your system and data safe.

Firewall: Firewall is in other hand a program which protects your system from outsider/intruder/hacker attacks. These attacks may not be virus type. In some cases hackers can take control of your system remotely and steal your data or important information from system. If your system is directly connected to internet or a large network than you can install a software firewall in your PC to protect your self from unauthorized access. Firewall is available either in software or in hardware form. For a single PC you may need a software firewall while a large corporate implements hardware firewall to protect all of their systems from such attacks.

Q5. What Is Loop Back?

Loopback address is 127.0.0.1, An address that sends outgoing signals back to the same computer for testing. 

Q6. What Are Gpos (group Policy Objects)?

A Group Policy Object (GPO) is a collection of settings that control the working environment of user accounts and computer accounts. GPOs define registry-based policies, security options, software installation and maintenance options, script options, and folder redirection options.

There are two kinds of Group Policy objects:

  • Local Group Policy objects are stored on individual computers.
  • Nonlocal Group Policy objects, which are stored on a domain controller, are available only in an Active Directory environment.

Q7. What Is Wins Server?

Windows Internet Name Service (WINS) servers dynamically map IP addresses to computer names (NetBIOS names). This allows users to access resources by computer name instead of by IP address. If you want this computer to keep track of the names and IP addresses of other computers in your network, configure this computer as a WINS server.

If you do not use WINS in such a network, you cannot connect to a remote network resource by using its NetBIOS name.

Q8. How Can We Remove Lingering Objects?

Windows Server 2003 and 2008 have the ability to manually remove lingering objects using the console utility command REPADMIN.EXE.

Q9. What Role Do Characteristics Such As Assertiveness And Problem Solving Play In The Career Of A System Administrator?

Analytical thinking and problem solving is crucial to be able to analyze software or hardware malfunction. They are also necessary to be able to improve or upgrade systems so that they suit company needs. Assertiveness also plays a role because administrators have to make decisions. They decide on solutions, security measures, and things like system upgrades.

Q10. What Is Active Directory?

Active Directory provides a centralised control for network administration and security. Server computers configured with Active Directory are known as domain controllers. Active Directory stores all information and settings for a deployment in a central database, and allows administrators to assign policies and deploy and update software.

Q11. How Do You Backup Ad?

Backing up Active Directory is essential to maintain the proper health of the AD database.

Windows Server 2003: You can backup Active Directory by using the NTBACKUP tool that comes built-in with Windows Server 2003 or use any 3rd-party tool that supports this feature.

Windows Server 2008: In Server 2008, there isn’t an option to backup the System State data through the normal backup utility. We need to use the command line to backup Active Directory.

@Open up your command prompt by clicking Start, typing “cmd” and then hit Enter.
@In your command prompt, type “wbadmin start systemstatebackup -backuptarget:e:” and press Enter.
@Input “y” and press Enter to start the backup process.

When the backup process has finished you should get a message that the backup completed successfully. If it did not complete properly you will need to troubleshoot.

Q12. Give An Example Of Systems You Have Been Working With As An Administrator?

These typically are: Windows and Linux, which support either Asset Management or GIS. Typical duties include engineering, support and maintenance, and research for the purpose of innovation and upgrading.

Q13. What Are The Personal Characteristics Of A System Administrator?

System administrators are experts at handling hardware and software. They are quick with both their hands and their head. They can work alone, but they know when and how to communicate with others, whether to report problems, learn information needed to fix problems, or instruct employees regarding technical issues.

Q14. What Is The Sysvol Folder?

The SYSVOL folder stores the server copy of the domain’s public files that must be shared for common access and replication throughout a domain.

All AD databases are stored in a SYSVOL folder and it’s only created in an NTFS partition. The Active Directory Database is stored in the %SYSTEM ROOT%NDTS folder.

Q15. What Are Lingering Objects?

A lingering object is a deleted AD object that still remains on the restored domain controller in its local copy of Active Directory. They can occur when changes are made to directories after system backups are created.

When restoring a backup file, Active Directory generally requires that the backup file be no more than 180 days old. This can happen if, after the backup was made, the object was deleted on another DC more than 180 days ago.

Q16. Differentiate Between Ntfs & Fat?

NTFS is the current file system used by Windows. It offers features like security permissions (to limit other users’ access to folders), quotas (so one user can’t fill up the disk), shadowing (backing up) and many other features that help Windows.

FAT32 is the older Microsoft filesystem, primarily used by the Windows 9X line and Window could be installed on a FAT32 parition up to XP. In comparision, FAT32 offers none of what was mentioned above, and also has a maximum FILE (not folder) size of 4GB, which is kind of small these days, especially in regards to HD video.

Q17. What Is Voip?

VOIP :Short for Voice Over Internet Protocol, a category of hardware and software that enables people to use the Internet as the transmission medium for telephone calls by sending voice data in packets using IP rather than by traditional circuit transmissions.

Q18. What Is Ldap?

A GLDAP (Light-Weight Directory Access Protocol) determines how an object in an Active Directory should be named. LDAP is the industry standard directory access protocol, making Active Directory widely accessible to management and query applications. Active Directory supports LDAPv2 and LDAPv3.

Q19. Why Should You Not Restore A Dc That Was Backed Up 6 Months Ago?

When restoring a backup file, Active Directory generally requires that the backup file be no more than 180 days old. If you attempt to restore a backup that is expired, you may face problems due to lingering objects.

Q20. What Is Domain Controller?

A domain controller (DC) or network domain controller is a Windows-based computer system that is used for storing user account data in a central database. It is the centrepiece of the Windows Active Directory service that authenticates users, stores user account information and enforces security policy for a Windows domain.

A domain controller allows system administrators to grant or deny users access to system resources, such as printers, documents, folders, network locations, etc., via a single username and password.

Q21. What Is Apipa?

Stands for Automatic Private IP Addressing

APIPA is a DHCP fail over mechanism for local networks. With APIPA, DHCP clients can obtain IP addresses when DHCP servers are non-functional. 

APIPA exists in all modern versions of Windows except Windows NT. When a DHCP server fails, APIPA allocates IP addresses in the private range 169.254.0.1 to 169.254.255.254.

Q22. What Is A Domain?

A domain is defined as a logical group of network objects (computers, users, devices) that share the same Active Directory database. A tree can have multiple domains.

Q23. What Do Forests, Trees, And Domains Mean?

Forests, trees, and domains are the logical divisions in an Active Directory network.

A domain is defined as a logical group of network objects (computers, users, devices) that share the same active directory database.

A tree is a collection of one or more domains and domain trees in a contiguous namespace linked in a transitive trust hierarchy.

At the top of the structure is the forest. A forest is a collection of trees that share a common global catalog, directory schema, logical structure, and directory configuration. The forest represents the security boundary within which users, computers, groups, and other objects are accessible.

Q24. What Is Garbage Collection?

Garbage collection is the online defragmentation of the Active Directory which happens every 12 hours.

Q25. What Is Proxy Server?

A proxy server is a computer that acts as a gateway between a local network (e.g., all the computers at one company or in one building) and a larger-scale network such as the Internet. Proxy servers provide increased performance and security. In some cases, they monitor employees’ use of outside resources.

Q26. What Is Group Policy?

Group Policy allows you to implement specific configurations for users and computers. Group Policy settings are contained in Group Policy objects (GPOs), which are linked to the following Active Directory service containers: sites, domains, or organizational units (OUs).

Q27. What Are Main Email Servers And Which Are Their Ports?

Email servers can be of two types:

Incoming Mail Server (POP3, IMAP, HTTP): The incoming mail server is the server associated with an email address account. There cannot be more than one incoming mail server for an email account. In order to download your emails, you must have the correct settings configured in your email client program.

Outgoing Mail Server (SMTP): Most outgoing mail servers use SMTP (Simple Mail Transfer Protocol) for sending emails. The outgoing mail server can belong to your ISP or to the server where you setup your email account.

The main email ports are:
POP3 – port 110
IMAP – port 143
SMTP – port 25
HTTP – port 80
Secure SMTP (SSMTP) – port 465
Secure IMAP (IMAP4-SSL) – port 585
IMAP4 over SSL (IMAPS) – port 993
Secure POP3 (SSL-POP) – port 995

Q28. Why Do We Use Dhcp?

Dynamic Host Configuration Protocol assigns dynamic IP addresses to network devices allowing them to have a different IP address each time they are connected to the network.

Q29. What Experience Do You Have With Hardware Components?

Installation and replacement are some of the most frequently performed operations with hardware. Sometimes a system administrator might need to rebuild a hardware component.