20 CentOS Interview Questions and Answers

CentOS is a popular Linux distribution that is often used for web servers and other applications. If you are applying for a position that involves working with CentOS, it is important that you are familiar with the operating system and can answer questions about it during an interview. In this article, we will review some common CentOS questions that you may encounter during your job interview.

CentOS Interview Questions and Answers

Here are 20 commonly asked CentOS interview questions and answers to prepare you for your interview:

1. What is CentOS?

CentOS is a Linux distribution that is derived from the source code of Red Hat Enterprise Linux (RHEL). CentOS is free to download and use, and it is one of the most popular Linux distributions for web servers and other enterprise-level uses.

2. Can you explain what the main features of CentOS are?

CentOS is a Linux distribution that is based on the Red Hat Enterprise Linux (RHEL) operating system. It is known for its stability and reliability, and is often used as a server operating system. CentOS is also free to download and use, making it a popular choice for many businesses and individuals.

3. Why should I use CentOS instead of Ubuntu or Fedora Linux?

CentOS is a stable and reliable operating system that is based on Red Hat Enterprise Linux. It is suitable for use in a wide variety of environments, from personal computers to servers. It is also free to download and use.

4. Is it possible to run CentOS on a virtual server? If so, how?

Yes, it is possible to run CentOS on a virtual server. You can use a tool like VMware or VirtualBox to create a virtual machine, and then install CentOS onto that virtual machine.

5. What is a good alternative for running CentOS in case I don’t want to install it on my system?

There are a few different ways that you can run CentOS without installing it on your system. One option is to use a virtual machine, which will allow you to run CentOS on your computer without actually installing it. Another option is to use a live CD, which will give you a temporary CentOS environment that you can use without installing anything on your system.

6. How can you get started with CentOS?

You can get started with CentOS by downloading the operating system from the CentOS website. Once you have downloaded the operating system, you will need to install it on your computer. Once you have installed CentOS, you can begin using it by logging into your account and following the on-screen instructions.

7. Can you explain some of the most commonly used commands in CentOS?

The most commonly used commands in CentOS are:

– yum: Used to install, update, and remove packages
– rpm: Used to manage packages
– service: Used to start, stop, and restart services
– chkconfig: Used to manage service configuration
– ifconfig: Used to configure network interfaces
– iptables: Used to configure firewall rules

8. What’s the best way to connect and manage a remote computer using CentOS?

The best way to connect and manage a remote computer using CentOS is to use a tool like SSH or PuTTY. With these tools, you can connect to the remote computer and then use a command line interface to manage it.

9. What are the disadvantages of using CentOS over other versions of Linux?

One of the main disadvantages of using CentOS is that it is not as widely supported as some of the other versions of Linux. This can make it more difficult to find help and resources when you are working with CentOS. Additionally, CentOS can be more difficult to work with when it comes to updates and security patches.

10. What is an advantage of using CentOS as a web server?

One advantage of using CentOS as a web server is that it is a stable and reliable platform. Additionally, CentOS is often used in enterprise environments because it is compatible with a number of different enterprise applications.

11. How do you create a new user account in CentOS?

You can create a new user account in CentOS by using the useradd command.

12. How do you assign sudo privileges to a user in CentOS?

You can assign sudo privileges to a user in CentOS by adding them to the sudoers file. You can do this by running the visudo command and then adding the user to the file with the appropriate permissions.

13. How do you disable root login in CentOS?

You can disable root login in CentOS by editing the /etc/ssh/sshd_config file and setting the PermitRootLogin parameter to no.

14. What is the procedure for installing MySQL on CentOS?

The procedure for installing MySQL on CentOS is as follows:

1. Download the MySQL Yum repository configuration file.
2. Install the MySQL Yum repository.
3. Install MySQL.
4. Start the MySQL service.
5. Secure the MySQL installation.

15. How do you upgrade CentOS from one version to another?

The process for upgrading CentOS from one version to another is relatively simple. The first thing you need to do is ensure that you have a current backup of your system. Once you have a backup, you can then begin the process of upgrading your system. The first step is to update your system’s repositories. Next, you will need to install any available updates. Once all of the updates have been installed, you can then begin the process of upgrading your system. The final step is to reboot your system to complete the upgrade process.

16. What is the process for upgrading Git on CentOS?

The process for upgrading Git on CentOS is to first ensure that all of your existing Git repositories are backed up. Next, you will need to uninstall the existing Git package using the yum package manager. Once that is complete, you will then install the new Git package. Finally, you will need to run the git init command to initialize any new repositories.

17. What is the command for starting up or shutting down Apache Web Server on CentOS?

The command for starting up Apache Web Server on CentOS is “service httpd start”. The command for shutting down Apache Web Server on CentOS is “service httpd stop”.

18. Where does CentOS store its installed packages?

CentOS stores its installed packages in the /var/cache/yum directory.

19. How do you find out which version of CentOS you’re running?

You can find out which version of CentOS you are running by running the command “cat /etc/centos-release”.

20. How do you check all the services that are running on CentOS?

You can check all the services that are running on CentOS by using the chkconfig command.