LPIC-1 (102-500): Certified Linux Administrator Interview Questions

The LPIC-1 (102-500): Certified Linux Administrator course is designed to match the real world of system administration: with its job task analysis surveys, the Linux Professional Institute determine what real sysadmins do on the job, and what skills they need. Therefore, to pass the interview round, you must showcase your ability to run Linux from a shell prompt, set up a Linux machine from scratch, and configure basic networking. Further, you need to have expertise in performing such tasks as running basic system administration commands on the command line, installing and configuring a Linux operating system, and setting up a network.

You may also go through our LPIC-1 (102-500): Certified Linux Administrator Online tutorial to further strengthen your knowledge base. Our Free Practice Tests will further help attain your desired certification and become competent to your employers in an ever-changing job market.

Everyone gets grilled during interviews. Even if you’re a seasoned expert, the questions you get asked at each new job will invariably be unique. But this doesn’t mean you’ll have to wing it when the time comes for your next interview. To help ease your post-interview nerves here’s a list of some of the more popular LPIC-1 (102-500): Certified Linux Administrator Interview Questions you may get asked. Let’s get started!

1. What is a Linux shell script?

A shell script is a text file containing a sequence of commands for a UNIX-based operating system. The name comes from the fact that it combines a sequence of commands that would otherwise have to be typed into the keyboard one at a time into a single script.

2. Could you differentiate between shell and bash scripting?

Bash stands for “Bourne Again Shell”, and is a better version of the original Bourne shell (sh). A shell script can be used in any shell, but Bash scripts may only be used in a Bash environment.

3. Could you explain the purpose of skeleton directories?

A skeleton directory is a directory used by popular hosting programs such as cPanel or Plesk to store default files and folders. To find this directory, log in to your server via WHM (Web Host Manager) in your browser. Type ‘skell’ into the search box(a), and this will sort the menu options for you.

4. How does the Shebang work in Linux?

The shebang —the first line of the script file— tells the kernel which program to use to run the program in a file. A shebang is any one-line comment that has the characters 

5. How would you define SUID permissions?

The SUID bit is called Set owner User ID. This bit is a special permission that applies to scripts or applications. When the SUID bit is set, when the command is run, its effective UID becomes that of the owner of the file instead of the user running it.

6. How would you define the X11 architecture?

The X Window System (aka X11) is a network protocol for displaying graphics on a variety of different hardware platforms. It has been implemented by a number of different vendors for a wide variety of hardware platforms. In Ubuntu, we ship X11 as implemented by the X.org project on Linux.

7. Is Wayland better than X11?

Wayland is more lightweight than X, as it avoids most of X11’s legacy baggage. One of the primary reasons for X11’s complexity is that its function has changed over the years. As a result, today, X11 widely serves as “a really terrible” communications protocol between the clients and the window managers.

8. How would you explain what Xorg does in Linux?

Xorg is an open-source X11-based desktop infrastructure. It is a piece of software that allows you to interact with your hardware and run graphical programs and applications. Xorg is also fully network-aware, meaning that you can run a program on one computer while actually viewing it on another.

9. What assistive technologies are available in Fedora and Ubuntu versions of Linux?

Ubuntu comes with a number of accessibility tools pre-installed and activated. The screen reader, magnifier, and on-screen keyboard can be activated using the Gnome Assistive Technology Preferences panel, found under System>Preferences in the Applications menu.

10. Could you explain a User Group in the database?

User groups are essentially database items that are used as a representation of a collection of user accounts. They’re designed to make it easier to manage the privileges and permissions of multiple user accounts at once. Typically, you create a user group to represent a collection of user accounts or sometimes even a department within your organization.

11. What is the difference between a job and a cron job?

By creating Kubernetes Jobs, transient pods can be created that perform specific tasks. A CronJob does the same thing, but it runs the tasks according to a defined schedule.

12. What do you mean by localization?

The process of localizing a product, application, or document refers to modifying its content to meet the linguistic, cultural, geographical, and other requirements of a specific market (a locale).

13. What is the difference between localization and Internationalisation?

Internationalization is the design of software so it can be adapted to various languages and regions. Whereas, localization is the actual adaptation of internationalized software for a specific region or language by translating text and adding locale-specific components.

14. How would you define the NTP Chrony?

Chrony is a free software package that allows computers to synchronize their clocks over the network, using the Network Time Protocol (NTP). It’s a replacement for the ntpd, which is a reference implementation of the NTP. Chrony runs on Unix-like operating systems (including Linux and macOS) and is released under version 2 of the GNU General Public License.

15. Can Chrony and NTP run together?

Yes, one can have multiple instances of Chrony on a computer at once. One can operate as an NTP client to synchronize the system clock and another as a server for other computers.

16. Could you highlight the functions of Syslog?

The System Logging Protocol (Syslog) is a standardized way for network devices to send out notifications in a standard message format. Syslog was designed to make it easy to monitor network devices. A Syslog agent, typically installed on the device, can send out notification messages under a wide range of specific conditions, such as when certain types of errors are spotted or when certain events happen.

17. What is meant by the Syslog configuration?

The Syslog daemon (Syslogd) provides a central location for logging messages generated by applications running on your Unix or Linux system. Its configuration file, /etc/Syslog.conf defines logging rules and output destinations for error messages, authorization violation messages, and trace data. Logging rules are defined using a facility name and a priority code.

18. What do you know about the CUPS command?

CUPS, a utility suite for managing printers, provides several commands to set up printers and make those printers accessible to systems on the network. In addition, CUPS supports several printer-specific options that enable you to control printer configuration.

19. What are the differences between IPv6 and IPv4 security?

Although IPv6 is designed with built-in encryption capabilities and packet integrity checking, IPv4 can be configured to offer similar security features, so there is essentially no difference between the two when it comes to Internet Protocol security (IPsec).

20. What are the basic TCP IP parameters?

◉ Hostname.

◉ DHCP client.

◉ Domain name.

◉ IP address.

◉ Netmask.

◉ Broadcast address.

◉ Default router.

21. Could you tell me what do Net-Tools include?

The net-tools package contains a collection of programs that form the base set of the NET- 3 network distribution for Linux. These tools control the network subsystem of the Linux kernel, including arp, hostname, ifconfig, netstat, rarp, and route.

22. What is the importance of the DNS servers?

The Domain Name System (DNS) is a server that is devoted to matching site names, such as example.com, to their corresponding Internet Protocol or IP addresses. The DNS server contains a database including the public IP addresses along with their corresponding domain names.

23. Could you tell me some of the safest DNS servers?

◉ Google Public DNS. IP Addresses: 8.8.8.8 and 8.8.4.4

◉ OpenDNS. IP Addresses: 208.67.220.220 and 208.67.222.222

◉ DNSWatch. IP Addresses: 84.200.69.80 and 84.200.70.40

◉ OpenNIC. IP Addresses: 206.125.173.29 and 45.32.230.225

◉ UncensoredDNS.

24. What are the advantages of shadow passwords over traditional password systems?

Shadow passwords store encrypted passwords in a location that is not readily accessible. Shadow passwords provide a number of benefits, including the ability to store encrypted passwords in /etc/shadow, instead of the unencrypted passwords used in most systems. 

25. What is the difference between shadow and Passwd?

The /etc/passwd and /etc/shadow files have different pieces of data. Passwd contains the users’ public information (UID, full name, home directory), while shadow contains the hashed password along with the password expiry date.

26. Could you define TCP wrappers and how they work?

TCP Wrapper allows users to control who may access their computers. The program monitors incoming packets and checks to see if any external entity is attempting to connect. If a connection attempt is detected, TCP Wrapper examines whether the external entity is authorized. If it is authorized for connection, access is permitted; if not, access is denied. The program can be customized to suit the individual user or network needs.

27. How would you define GPG configuration?

GPG.conf is the configuration file that GPGreads on startup. This file may contain any valid long option, but the leading two dashes must not be entered and the option may not be abbreviated. This default name may be changed on the command line (GPG-option –options). You should backup this file.

28. How do GPG encryption and decryption work?

To send someone a secret message, you encrypt it using their public key. They then decrypt the message using their private key. The encrypted message and the short key are sent to the recipient who decrypts them using their own private key.

29. Is GPG encryption secure?

GPG is very secure, as long as you choose a strong enough passphrase. In practice, your passphrase will almost always be the weakest link. This instructs GPG to use a password hashing method that is slow enough to make brute-force guessing impractical, but only if you enter your passphrase on every operation.

30. Could you elaborate on the SSH port tunneling?

SSH tunneling makes it possible to transport arbitrary data over an encrypted SSH connection. It can be used to forward connections made to a port on your own desktop to a remote machine via a secure channel.

Source: testpreptraining.com