Linux Administrator Interview Questions and Answers

Linux Administrator Interview Questions and Answers

Linux is most used free open source operating system (OS). As an operating system, Linux is software that sits underneath all of the other software on a computer, receiving requests from those programs and relaying these requests to the computer’s hardware.

We use the term “Linux” to refer to the Linux kernel, but also the set of programs, tools, and services that are typically bundled together with the Linux kernel to provide all of the necessary components of a fully functional operating system. Some people, particularly members of the Free Software Foundation, refer to this collection as GNU/Linux, because many of the tools included are GNU components. However, not all Linux installations use GNU components as a part of their operating system. Android, for example, uses a Linux kernel but relies very little on GNU tools. Some of the most popular and mainstream Linux distributions are Arch Linux, CentOS, Debian, Fedora, Gentoo Linux, Linux Mint, Mageia, openSUSE and Ubuntu, together with commercial distributions such as Red Hat Enterprise Linux and SUSE Linux Enterprise Server. Linux was originally developed for personal computers based on the Intel x86 architecture, but has since been ported to more platforms than any other operating system. Because of the dominance of the Linux kernel-based Android OS on smartphones, Linux has the largest installed base of all general-purpose operating systems. Linux is also the leading operating system on servers and other big iron systems such as mainframe computers, and the only OS used on TOP500 supercomputers (since November 2017, having before gradually eliminated all competitors).

First Linux is released on September 17, 1991, by Linus Torvalds, a then-student at the University of Helsinki. Torvalds built Linux as a free and open source alternative to Minix, another UNIX clone that was predominantly used in academic settings. He originally intended to name it “Freax,” but the administrator of the server Torvalds used to distribute the original code named his directory “Linux” after a combination of Torvalds’ first name and the word UNIX, and the name stuck.

Linux System Administrator responsibilities:

  • The Linux system administrators are responsible for installing, configuring and maintaining the Linux servers and workstations. They are responsible for maintaining the network environment as well as the health of the network and servers.
  • The Linux system administrators need to participate in various cross training activities, so as to achieve a comfort level that supports the database. They may also be involved in training the subordinate team members in system administration and software deployment responsibilities.
  • Installing and configuring server and Creating and maintaining user accounts
  • Evaluate all documents according to system requirements and evaluate all design and perform tests on all development activities and administer all complex methodologies.
  • Develop an infrastructure to provide support to all business requirements and perform regular troubleshoot on system to resolve all issues.
  • Monitor everyday systems and evaluate availability of all server resources and perform all activities for Linux servers.
  • Configuring a secure system; it is a duty of administrator to involve tasks and decisions to run secure Linux system and maintaining data integrity. Resolve all issues across various technologies and design require enterprise servers and provide back up support. It perform tests on all new software and maintain patches for management services
  • Administrator all performance for various resources and ensure optimization for same and provide support to all applications and ensure optimal level of customer services.
  • It performs troubleshoot on all tools and maintain multiple servers and provide back up for all files and script management servers.

What is Linux system Administrator?

What is kernel?

What is Shell?

What is the Minix?

What is POSIX?

What is name of first process in Linux?

Who initiated the GNU Project?

What is the use of sysctl command?

Explain the procedure for re-installing Grub in Linux?

What is the use of DAS, NAS and SAN?

What is SAS?

What is Initrd?

What is Bootloader?

What is a Zombie?

What is Swap Space or swap file?

What is MX Record?

What is CUPS?

What is Soft Link?

What is LVM?

What is RAID?

What are run levels in Linux?

What are inodes in Linux? How to find the inode associated with a file?

What neat command will do?

What is the functionality of a Puppet Server?

How to create simple shell scripts in Linux?

What is SeLinux?

Explain the terms of SUID, SGID and sticky bit?

How to disable user login via terminals?

What is the role of /etc/resolv.conf file?

The option Open in Terminal is missing when user right clicks on terminal in GUI. How to fix this?

How do you disable the NetworkManager service on runlevel 5?

What is Drop cache in Linux?

How do you find out all the packages installed on a RHEL system (server)?

How to check the default gateway?

What is the minimum number of partitions you need to install Linux?

What are the process states in Linux?

What are different backup techniques?

What is YUM?

What happens when you run the rm command?

Which Linux service is used as a database server?

Which Linux service is used to turn a Linux system in proxy server?

How to check the ip address of LAN card?

What is the difference between umask and ulimit?