Do you have your Linux Interview in the upcoming days? Here is the comprehensive guide by MindMajix that will help you ace your Linux Interview Rounds easily. I have covered all types of Linux Questions in multiple categories. It will give you all the insights into the questions that you may face in your Interviews. By the end of this guide, you will have enough confidence to excel in the interview quickly. So, what are you waiting for? Let us start.
In today’s world, which is more about automation, microservices, and advanced deployment methods, Linux plays a crucial role. Almost all organizations across the globe use the Linux Operating System for managing their system. Also, by 2032, the Linux Operating System market is expected to reach around USD 24 billion as stated in the report by Allied Market Research. Therefore, it is evident that the industry is full of opportunities in Linux development. So why not take advantage of these?
If you want to become a Linux developer in a reputed organization, this blog will help you. We will cover all the topics from basic Linux commands to advanced concepts like File Management so that you can easily crack your Linux Interview Round.
Table of Contents
Before moving straight to the interview questions, it is important to know its overview and history so that we can understand its use in a better way!
Linux is a Unix-like operating system. It was developed as an open-source project to provide users with a stable, customizable, and cost-effective platform for computing. It has been used as an alternative to operating systems like Windows and macOS which are not open source. It has a modular design due to which it can extend the software packages available for Linux. Thus, we can easily customize according to our own requirements.
Linus Torvalds, who was a Finnish computer science student developed Linux as an open-source project. It was developed as an Operating System similar to Unix. After development, its initial version 0.01 was released as open-source software under the GNU General Public License (GPL). Thus, it got huge contributions, bug fixes, and improvements from the global community of developers. It has a wide range of applications like server administration and network management. With these benefits, Linux has become a crucial part of the modern software development environment.
The Linux Developers with 1-2 years of Experience are expected to deliver the strong fundamental skills such as:
With more than 5 years of Experience, you are expected to deliver the following skills and responsibilities:
Ans: Linux is an operating system, which is based on the Linux Kernel. It is an open-source operating system that can be used with different hardware platforms. As it is an open-source OS, it provides a free and low-cost operating system for users. It is a user-friendly environment where they can easily modify and create variations in the source code.
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Ans: The key feature of Linux is that it is open source, which allows users to access, modify, and distribute the source code freely. Also, it has a modular architecture, security features like user permissions and access controls, networking support, and a command-line interface.
Ans: Linus Torvalds created Linux. Linus Torvalds was a student at the University of Helsinki, Finland in 1991. He started writing code on his own to get the academic version of Unix for free. Later on, it became popular as Linux Kernel.
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Ans: Here is the difference between Linux and Unix - mentioned below
Linux
|
Unix
|
Both paid and free distributions are available. | Different paid structures for different levels of Unix. |
Linux primarily uses GUI with an optional command-line interface | Unix uses the command-line interface |
Linux OS is portable and can be executed on different hard drives | Unix OS is not portable. |
Linux is developed by a worldwide Linux community. | Unix is developed by AT&T developers. |
Linux is free. It is downloaded through the internet under GNU licenses. | Most Unix-like operating Systems are not free. |
Linux is used at home-based PCs, phones, etc. | Unix is used in server systems. |
Ans: The Root user is the superuser or administrator who has unrestricted access to all system resources and commands. Root privileges allow this user to execute administrative tasks, install software, modify system configurations, and manage user accounts.
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Ans: Linux kernel is the heart of the operating system. It acts as a bridge between software and hardware. If Software requests the hardware, then the kernel delivers the data between software and hardware. In other words, the hardware and software components communicate with each other through the Kernal. .
Ans: Bash is a Unix shell and command processor written by Brian Fox for the GNU project. It is free software and acts as a replacement for Bourne Shell. It is an interpreted and not compiled process which can also be run in the terminal window. Bash is capable of reading commands from shell scripts.
Ans: LILO means Linux Loader is a boot loader that is used for the Linux operating system. Most of the Linux Operating systems use LILO, to boot the operating system into the main memory to start the operations.
Ans: CLI means Command language Interpreter. It interacts with the computer program, where the user issues commands in the form of text lines. It Interacts with the computer terminals also, the interface accepts the text lines and converts them as a command to the operating system.
Ans: Linux Distribution means the complete operating system containing the Linux Kernel and collection of the software applications, utilities, libraries, and system tools. Each distribution includes a package management system for installing, updating, and removing software packages. Therefore, every Linux Distribution has a unique set of configuration tools and documentation for specific requirements.
Ans: The Latest version of Linux is the Linux Mint 21.3 "Virginia." It was released on January 12, 2024, as the LTS (Long Term Support) release. Linux Mint is one of the most popular distributions that provides the desktop computing experience. We can select the pre-installed software applications, including web browsers, office suites, multimedia players, and system utilities, due to which it is considered as user-friendly.
Ans: Linux was one of the first open-source technologies, many programmers added software that completely open to the users, which means you can download the file and change the code as you like. It has a wide range of options for users and increased security.
Ans: Disadvantages of Open Source Operating System mentioned below
Ans: Shell is a computer program that acts as an interface between the user and the kernel. Users can communicate with the kernel by writing programs, commands, and scripts on the shell. It accepts human-readable commands and converts them into kernel-understandable language.
Ans: They are five Shells in Linux:
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Ans: Basic components of Linux
Ans:
Launch your terminal by pressing CTRL+ALT+T or by giving terminal in the menu search bar.
Ans: Swap Space is used when the physical RAM memory is running out. It will move the RAM inactive pages to the swap space. It can be considered in the form of a dedicated swap partition or swap files.
Ans: GUI means Graphical User Interface. It is a human-computer interface that uses windows, images, icons, and menus which can be manipulated by using a mouse. Most of the modern applications in electronic gadgets communicate with the user through GUI. GUI is a combination of graphical and textual interaction that uses buttons, menus, message boxes, etc.
Ans: Linux file permissions - Each file or directory has 3 permissions
They are
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Ans: In Linux, environmental variables are dynamic values that define the operating environment for processes and applications. They include system-wide settings such as PATH, HOME, and LANG, influencing how programs behave and interact with the system. These variables can be viewed, modified, and exported using commands like export and echo.
Ans: Symbolic links, also known as symlinks or soft links, are filesystem objects that act as pointers or references to other files or directories. Unlike hard links, which directly reference the inode of the target file, symbolic links store the path to the target file or directory.
Syntax:
ln -s <target> <link_name>
For example, if you want to create a symbolic link named docs in your home directory that points to a directory named documents located in /mnt/data, you would use the following command:
ln -s /mnt/data/documents ~/docs
Ans: Hard links are directory entries that directly point to the inode of a file or directory on a filesystem. They share the same inode as the target file. This means that changes to the original file are reflected in all hard links pointing to it, and vice versa.
Syntax:
ln <target> <link_name>
Suppose you have a file named file1.txt in your home directory and you want to create a hard link named file2.txt in the same directory that points to file1.txt, you would use the following command:
ln ~/file1.txt ~/file2.txt
Ans: Redirection can be defined as changing the standard input and output devices. To redirect metacharacters are used, you can redirect the file or program. We can various types of redirection in Linux Like:
Standard Input (stdin) Redirection (<): Redirects input from a file to a command. You take data from a file and pour it into a command.
Syntax: command < input.txt
Standard Output (stdout) Redirection (>): Redirects output from a command to a file, overwriting existing content. It means that you take the output from a command and pour it into a file, replacing any existing content.
Syntax: command > output.txt
Appending Output (>>): Take data from the command to a file without removing the existing content. It just appends to existing content.
Syntax: command >> output.txt
Piping (|): Redirects output from one command as input to another command. Thus, You take the output from one command and connect it to the input of another command.
Syntax: command1 | command2
Standard Error (stderr) Redirection (2>): Redirects error messages from a command to a file. Using this, we can take error messages from a command and pour them into a file.
Syntax: command 2> error.txt
Ans: Daemons are background processes in Unix-like systems. They perform tasks independently of user interaction. Examples of the Daemons include sshd for secure remote access and cron for scheduled tasks. Thus, Daemons ensure system functionality and handle essential operations.
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Ans: The root is the user name, which by default has access to all files and commands. The root user can do many things, but an ordinary user cannot do things like installing software, changing file permissions, etc. To change the root user, you can use the command ‘sudo su ’ and enter the password as shown below:
Ans: The root is the user name, which default has access to all files and commands. The root user can do many things, but an ordinary user cannot do like installing software, changing file permissions, etc.
Ans: Virtual Desktop is a user interface when you are facing the problem of how to manage multiple windows on your desktop, virtual desktop serves as an alternative. Virtual desktops store remote servers and allow you to use one or more programs on a clean slate.
Ans: There are three kinds of modes in vi editors. They are
Ans: The inode (index node) is a data structure that stores metadata about a file or directory, excluding its name and actual data content. On the other hand, the process ID (PID) is a unique numerical identifier assigned to each running process.
When a program is executed, the operating system assigns it a PID, which serves as a reference point for identifying and managing the process. To view the inode content of a file or directory in Linux, you can use the ls command with the -i option.
Syntax:
ls -i <filename_or_directory>
Ans: Five process states in Linux. They are
Ans: Process management system calls in Linux are a set of functions that enable the creation, termination, and manipulation of processes, as well as facilitate communication and synchronization between processes.
Ans: The File Permissions define the access rights for different categories of users: the file owner, the group associated with the file, and others. There are three user-based permission groups for each file and directory. They are:
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Ans: Linux file system stores and handles the data. Without a file system, it cannot know where the file starts from and where the file ends. In simpler words, the file system in Linux defines how data is organized and accessed, including the hierarchy of directories, file naming conventions, permissions, and metadata associated with each file and directory.
Ans: The different types of file systems in Linux are:
Ans: LVM stands for Large Volume Management, it is a storage management device. Users can create, resize, and delete LVM partitions. It increases abstraction, flexibility, and control. LVM is used to gather existing storage devices into the group and allocate logical units.
Ans: The purpose of the screen command in Linux is to create and manage multiple terminal sessions within a single terminal window or SSH session. It allows users to create "screens" or virtual terminal windows that can run independently of each other, even if the original terminal session is disconnected.
Ans: unmask stands for user file creation mode. When the user creates any file, it has default file permissions. So unmask will specify a few restrictions to the newly created file (it controls the file permissions). To implement umask, you have to use the command
umask [-S] [mask]
For example, to set the umask to 022, which removes write permissions for group and others, we can use the following commands:
umask 026
Ans: If the unmask command invoked without any arguments, it means it will display the current mask.
To set the unmask permanently, we have two types.
They are:
Ans: Network Bonding is a process of combining more than two network interfaces to form a single network interface. It offers performance improvement and redundancy by increasing network throughput and bandwidth.
Ans: Different modes of Linux network bonding
Ans: To display the default route and routing table, we use the following commands.
$ route-n
$ nestat-rn
$ ip
Ans: Here are several commands using which we can check on the open ports in the Linux Server. They are:
Ans: The location of the directory that stores the kernel modules is “lib/modules/kernel-version/” It stores all the information about the compiled drives under the Linux system. Using the ‘lsmod’ command also we can see the installed kernel modules
Ans: The init is a traditional initialization system used in older Unix-like systems, executing startup scripts sequentially. An example command to restart a service using init is "service <service_name> restart".
On the other hand, systemd is a modern initialization system designed for faster boot times and advanced service management. An example command to restart a service using systemd is "systemctl restart <service_name>".
We should use the init for simple environments and systemd for the parallel startup and dependency management in modern Linux distributions.
Ans: The role of a Linux firewall is to monitor and control incoming and outgoing network traffic based on predefined security rules. It acts as a barrier between the internal network and external networks, such as the Internet, to protect against unauthorized access, malware, and other security threats.
We have to follow the below steps for its configuration:
Ans: To change the default run level in Linux use the init command.
Ans: To share a directory using NFS, first edit the configuration file and ‘/etc/exports’ and add an entry like directory name ‘/<directory-name>’. Now restart the NFS service.
Ans: Details mentioned below
Service
|
Port
|
SMTP
|
25
|
DNS
|
53
|
FTP
|
20(Data Transfer) 21(Connections Established)
|
DHCP
|
68(dhcp client), 67(DHCP server)
|
SSH
|
22
|
Squid
|
3128
|
Ans: Locking user accounts is done for security purposes so that unauthorized users cannot log in. So, we have a few ways to lock the user account. Some of them are below
Ans: It is one of the basic commands in Linux. It is used to list all the files and directories in the file system.zom
Syntax:
ls [OPTIONS] [FILES]
We can use it without passing the arguments, then it will list all the files in the current working directory. Files will be displayed in alphabetical order.
Is
To list the specific directory files use the directory name in the syntax, follow as shown in the below syntax.
ls /etc
We can also pass multiple directories names in the syntax, but separated by space.
ls /etc /var /etc/passwd
Ans: The Tail command print the last N number of lines of the given data, it prints 10 lines by default.
Syntax:
tail [OPTION]... [FILE]
Example:
$ cat names.txt
Tableau
sql server
linux administration
Now, check the syntax without giving any option or input.
$ tail state.txt
Ans: The grep searches file patterns. If you are looking for a specific pattern in the output of another command, grep highlights the relevant lines. Use this grep command for searching log files, specific processes, and more
Syntax:
grep [options] pattern [files]
For example, to search for the specified "pattern" within the file "filename.txt" and display all lines containing that pattern, you can use the following command.
grep "pattern" filename.txt
Ans: The ps command displays the current process status of the system. And it displays the process id’s with some other related data also
Syntax:
Ps [options]
Output:
[root@rhe17~]# ps
PID TTY TIME CMD
12330 pts/0 00:00:00 bash
21621 pts/0 00:00:00 ps
Example: This command displays a detailed list of all processes running on the system, including user, PID, %CPU, %MEM, and command.
ps -aux
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Ans: env is a shell command is used to print a list of current environmental variables and it can run another process in another environment without any modification of the current environment.
env [OPTION]... [-] [NAME=VALUE]... [COMMAND [ARG]...]
Example: The ‘env’ command will print all the environment variables currently set in the shell.
Options
Tag
|
Description
|
-i, --ignore-environment
|
Start with an empty environment.
|
-0, --null
|
output line End with a 0 (null) byte rather than a newline.
|
-u, --unset=NAME
|
removes variable NAME from the environment
|
--help
|
Display a help message and exit.
|
Ans: The top command is used to show the system process and it displays and updates the sorted process information.
Syntax:
top [options]
Example:
top -n 1
Here, the ‘-n 1’ option specifies that the top should only run once and then exit, displaying system information once.
Ans: The netstat command gives various information about the network and routing tables, interface statics, and more about the system.
Syntax:
netstat [options]
Example:
The ‘netstat -tuln’ command will display all listening TCP and UDP sockets along with their respective numerical addresses and port numbers.
Ans: lsof means List of files, we can know which file is opened by which process.
lsof [options]
Example:
The below command lists all open files and network connections, including those associated with port 80.
lsof -i :80
Ans: This command is used to change the permission of files and directories. Therefore, on the whole, there are three types of permission, read, write, and execute, and are represented by numbers as shown below.
syntax:
$ chmod options permissions file name
$ chmod [OPTION]... MODE[,MODE]... FILE...
$ chmod [OPTION]... OCTAL-MODE FILE...
$ chmod [OPTION]... --reference=RFILE FILE…
For example, to give read and write permissions to the owner of a file named "example.txt" while allowing only read permission to the group and others, you would use the following command:
chmod 644 example.txt
Here, the first digit (6) represents the permissions for the file owner (read + write = 4 + 2).
The second and third digits (4) represent the permissions for the group and others. Thus, both are set to read-only.
Ans: Chown command: The command “chown” stands for change file owner and Group. This command is used to change the ownership of one or more files or folders for a specified user or group.
syntax:
$ chown [OPTION]… [OWNER][:[GROUP]] FILE…
Or
$ chown [OPTION]… –reference=RFILE FILE…
Suppose you want to change the ownership of a file named "example.txt" to a user named "john" and a group named "users", you would use the following command:
chown john:users example.txt
Ans: The cp command is used to copy files and directories. It is also used to backup files or directories.
Syntax:
$ cp filename
Example: The command “cp file1.txt file2.txt” copies the contents of file1.txt into file2.txt, creating file2.txt if it does not exist, or overwriting it if it does.
Ans: rm command: The rm command is used to remove the directory or file specified on the command line. You need to be careful while removing any file or directory.
Syntax:
rm filename---
Command
|
Description
|
rm filename
|
Removes single file.
|
rm filename1, filename2, filename 3
|
Removes multiple files.
|
rm * .pdf
|
Removes all pdf files in the current directory.
|
rm -i filename(s)
|
-i mean to confirm before deleting the file
|
rm -f filename(s)
|
Removes files without prompting
|
rm -fv *.txt
|
Remove all .txt files in the current directory without prompting
|
Ans: mkdir, command allows users to create directories in Linux. Users can create multiple directories at once and can set the permissions to the directories.
Syntax:
mkdir [options...] [directories ...]
Option
|
Description
|
Directory
|
name of the directory to be created
|
-m=mode, --mode=mode
|
to set a file mode (permissions, etc.) for the created directories
|
-p, --parents
|
create parent directories
|
--v, --verbose
|
Verbose output. Print a message for the created directory.
|
--Z= context, --context=context
|
If you are using SELinux, this option sets the security context of each created directory to context.
|
--help
|
shows help message and exit
|
--version
|
It shows version information and exit
|
Ans: The rmdir command in Linux is used to remove empty directories from the filesystem.
Syntax:
rmdir [-p] [-v | –verbose] [–ignore-fail-on-non-empty] directories
Where:
Example:
rmdir -p -v --ignore-fail-on-non-empty mydirectory
The above command removes the specified directory named "mydirectory" and its parent directories if they are empty. It displays a message for each directory removed and ignores any error messages if a directory is non-empty.
Ans: We can use two commands to exit from the vi editor. They are
Ans: The following commands are used to delete information from a file in vi editors.
Ans: File content commands
Ans: We have three types of Linux Distributions namely:
If we talk about the Linux Distributions, the most popular ones are:
Ans: We are many reasons, in that few important reasons are listed out. Following are
Ans: Following are the features of the Linux Operating System
Ans: Difference between Bash and Dos
Bash | Dos |
Commands are case sensitive | Commands are not case-sensitive |
Backward slash(/) represents directories separator | ‘/’ represents command arguments |
Forward slash ‘’ represents the escape character | ‘’ represents directories separator |
Does not follow conventions naming in files | Follow naming convention in files |
Ans: Internal Commands are the Commands directly run by the shell known as internal commands and there is no separate process to run the commands. Examples include cd, echo, pwd, and history.
On the other hand, the External Commands are the Commands which are run by the kernel and are known as external commands and every single command has its unique process id. ls, grep, cat, and rm.
Ans: It is a form of redirection that is used in Linux, it is used to combine more than two commands and the output of one command can take as input to the next command.
Syntax:
command_1 | command_2 | command_3 | .... | command_N
Example:
ls | grep example
This command first executes ls to list all files and directories in the current directory, and then pipes the output to grep, which filters the output to display only the lines containing the word "example".
Ans: Communication between a parent process and its child process in Linux can be achieved through various inter-process communication (IPC) mechanisms. These mechanisms allow processes to exchange data, synchronize their actions, and coordinate their execution. The types of IPC mechanism in Linux are:
Ans: It is a centralized server that does not have any exists states on the working station. It may have scenarios when a state of a particular system takes a snapshot then, the user wants all other machines to be in that particular state.
Ans: Features of Stateless Linux Server
Ans: It is a process whose execution is completed but even the information exists in the process table. It occurs for the child process because the parent process needs to read the child process status. Once it is completed using the wait system call, then the zombie process is removed from the process table.
Ans: In Linux, the Ctrl+Alt+Del key is used to restart the computer, and it does not display any confirmation message before rebooting the system.
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Ans: Linux is an open-source operating system, nowadays it is rapidly growing in the technology market. We have a few reasons why Linux is more secure than other OS.
Ans: The tail command displays the last part of a file. Generally, users don't need every logline to troubleshoot. Instead, you want to check what your logs say about the most recent request to your application.
tail Example:
$ tail -n 100 /var/log/httpd/access_log
Ans: In Linux cat command concatenates and prints files. Users might issue cat to check the contents of your dependencies file or to confirm the version of the application that you have already built locally.
cat Example:
$ cat requirements.txt
flask
flask_pymongo
Ans: grep searches file patterns. If you are looking for a specific pattern in the output of another command, grep highlights the relevant lines. Use this grep command for searching log files, specific processes, and more.
grep Example:
$ cat tomcat.log | grep org.apache.catalina.startup.Catalina.start
12-Jan-2018 17:08:35.542 INFO [main] org.apache.catalina.startup.Catalina.start Server startup in 681 ms
Ans: ps command displays process status. Use this ps command to determine a running application or confirm an expected process.
ps Command Example:
$ ps -ef
$ ps -ef | grep tomcat
Ans: env command allows users to set or print the environment variables. During troubleshooting, users can find it useful for checking if the wrong environment variable prevents your application from starting.
env Command Example:
$ env
PYTHON_PIP_VERSION=9.0.1
HOME=/root
DB_NAME=test
PATH=/usr/local/bin:/usr/local/sbin
LANG=C.UTF-8
PYTHON_VERSION=3.4.6
PWD=/
DB_URI=mongodb://database:27017/test
Ans: top command displays and updates sorted process information. Use this top command to determine which processes are running and how much memory and CPU they are consuming.
Ans: netstat command in Linux shows the network status. This netstat command shows network ports in use and their incoming connections.
Ans: ls of command lists the open files associated with your application.
Ans: Users can use the df command to troubleshoot disk space issues. Here df stands for display free disk space.
Syntax:
df [options] [file|directory]
df Command Example:
df -h
Here, the -h option is used to display the output in a human-readable format like kilobytes (K), megabytes (M), gigabytes (G), etc.
Ans: The du command in Linux is used to retrieve more detailed information about which files use the disk space in a directory.
Syntax:
du [options] [file|directory]
du Command Example:
$ du -sh /var/log/*
1.8M /var/log/anaconda
384K /var/log/audit
4.0K /var/log/boot.log
0 /var/log/chrony
4.0K /var/log/cron
4.0K /var/log/maillog
64K /var/log/messages
Here, the -s displays only a summary of total disk usage for each specified directory, and the -h: Displays output in a human-readable format (e.g., kilobytes, megabytes, gigabytes).
Ans: iptables command blocks or allow traffic on a Linux host, similar to a network firewall. This iptables command may prevent certain applications from receiving or transmitting requests
Syntax:
iptables [options] [chain] [rule]
The following options are available for the iptables:
For example, the following command adds a rule to the INPUT chain to drop all incoming traffic from the IP range 192.168.1.0/24.
iptables -A INPUT -s 192.168.1.0/24 -j DROP
Ans:
Linux | Windows |
Linux is available for FREE | It is paid software |
It is an Open-Source operating system | It is not an open-source OS |
Linux customization is possible | No customizations are available |
It provides high-level security | Can't defend against virus and malware attacks unless it is paid |
Primary partitioning and logical partitioning available for boot | Booting is available while primary partitioning only |
BackSlash separates directories | The forward slash separates directories |
File names are case-particular | Irrespective of the case while naming files |
Ans: cd- command go to the previous directory.
Ans: Go to $HOME directory
Ans: The command (cd /var/log && ls -l) changes the directory to /var/log, lists the contents of the directory using ls -l, and then returns to the original directory
Example:
(cd /var/log && ls -l)
In this example, the command first changes the directory to /var/log, lists the contents of the directory using ls -l, and then returns to the original directory (/home/user).
Ans: The pushd command in Linux puts the current directory on the directory stack, allowing you to navigate between directories efficiently.
Syntax:
pushd [directory]
Example:
pushd /var/log
Ans: The ls -lSr command in Linux is used to list files and directories in the current directory in long format (detailed listing) sorted by size in descending order (largest size first).
Ans: This command is used to display the top disk space users in the current directory. Let us understand it's working in the following way:
Ans: This command sort path by easy to interpret disk usage.
Ans: This command shows free space on mounted file systems. The df -h command in Linux is used to display free space on mounted file systems in a human-readable format. It provides information about the total disk space, used space, available space, and usage percentage for each mounted file system.
Ans: The df -T command in Linux is used to display information about disk space usage in the system along with the filesystem type for each mounted filesystem
Ans: The fdisk -l command in Linux is used to display the sizes and types of disk partitions on the system. It lists information about all available disk partitions, including their sizes, types, and start and end sectors. This command must be run as root (sudo fdisk -l) to display partition information.
Ans: To kill a program using a specific port in Linux, you can use the fuser command with the -k option followed by the port number and protocol (TCP or UDP). For example, to kill a program using port 8000, you would use:
sudo fuser -k 8000/tcp
Ans: The ulimit command allows us to limit memory usage for commands in Linux. By setting the virtual memory size (in kilobytes), you can restrict the memory usage of a command.
Syntax:
ulimit -Sv [memory_limit]
Example:
ulimit -Sv 1000
This command limits the memory to 1000 KBs (1 MB)
Ans: You can use the following commands to get the full path:
Ans: We can use the below commands to view and extract single file for tar file
tar tf file.tgz
tar xf file.tgz filename
Ans: To find out who is currently logged in to the system, you can use the w command which displays the users as shown below:
Ans: It is useful to detect permissions errors, for example when configuring a web server. So, to check the permissions of each directory leading to a file, you can use the namei command with the -l option followed by the path to the file.
namei -l /path/to/file.txt
Ans: To run a command every time a file is modified, you can use a combination of the inotifywait command and a loop.
Example:
while inotifywait -e close_write document.tex
do
make
done
Ans: we can use the command ‘cat file.txt | xclip -selection clipboard’ to copy the text to the clipboard.
Ans: This is an important Linux Interview Question to test your understanding of the Linux Development Environment. We can use the command /usr/bin/time -v ls to check the resource usage in the Linux File System.
Ans: To run a command for a limited time, you can use the timeout command followed by the duration and the command you want to run. An example of this command is given below
timeout 10s ./script.sh
Ans: Use this command: comm file1 file2.
Well, the time to learn Linux depends on the individual's learning capacity. However, MindMajix offers a Linux Networking Course that can help you learn Linux Networking within 30 hrs of the session, and 25 hrs of Lab Access to do hands-on practice on the Linux commands. With continuous practice on a daily basis, you can easily complete the Linux course by MindMajix.
It is obvious that acquiring the knowledge to become a lot of Linux System Admin requires practice. So, create a roadmap and stick to it. Try to learn and practice at least 3-4 commands every day. And, if you are stuck somewhere, reach out to the Linux Community for support. Also, RHSA(Red Hat Certified System Administrator) certification can also help you to gain strong expertise in Linux administration.
The basic roles and responsibilities of the Linux Administrator:
The above insights are sufficient for you to understand the importance of the Linux administrator so that you can deliver your best work as the Linux Admin.
Since the Linux System is often integrated with other platforms and systems, you should have a good understanding of scripting languages like Python or Perl for automation and tooling. You should also have Knowledge of version control systems such as Git for managing codebase changes. Also, Docker and Kubernetes, as they are widely used in modern Linux-based environments, can help you to achieve higher growth over Linux development.
Knowing about the L1(Level 1) , L2(Level 2) and L3((Level 3) in the Linux Administration will help you to clearly understand your roles and responsibilities in the team. L1, L2 and L3 are the support levels in Linux that allows us to provide the technical assistance provided to users according to requirement.
L1 Support is the First-line support or helpdesk support in which we handle basic user inquiries and technical issues. L2 Support deals with more complex technical issues that require deeper understanding of systems and infrastructure. Finally, L3 provides fixes for highly complex technical issues like kernel debugging, performance optimization, and security hardening.
Wrapping up what we learned, Linux has become an important component of most modern Infrastructures, system administration, cloud computing, cybersecurity, software development, etc. Hence, you can explore multiple career opportunities in the IT Industry. The above most asked Linux Interview Questions would help you to gain expertise in Linux Kernel Development. So, you can easily gain expertise on Linux through this blog by MindMajix and grow your career as a Linux Developer.
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Usha Sri Mendi is a Senior Content writer with more than three years of experience in writing for Mindmajix on various IT platforms such as Tableau, Linux, and Cloud Computing. She spends her precious time on researching various technologies, and startups. Reach out to her via LinkedIn and Twitter.