15 September

Use of comm and diff commands in Linux

Linux offers two commands to compare the text written within files: comm and diff. In this article we focus on the use of comm and diff commands in Linux and understand the difference in the output by each. comm command in Linux The comm command is used to compare two sorted files. The output contains […]

02 September

How to use the sort command in Linux?

We use the sort command in Linux to sort the content of a file. The sorted output is displayed on the screen. Syntax of sort command $sort [OPTION]… [FILE]… Example Options used with sort command -f: ignore case                 This option sorts the uppercase alphabets higher in order. The figure below shows the use of […]

07 June

Logical Volume Management in Linux

Logical Volume Management (LVM) in Linux is a method to easily manage disk space. Suppose as an admin you have three disks: 60Gb, 50Gb and 40Gb and you want to allocate 80Gb and 70Gb of space to two users U1 and U2 respectively. Now, there is no single unit of either size available. This is […]

26 May

Managing Swap Space in Linux

Swap space is an area in the secondary storage device which is used to supplement system RAM by holding the inactive pages of memory. The combination of system RAM and swap space is referred to as Virtual memory. When the available RAM usage exceeds a specified limit then the kernel will write idle pages belonging […]

18 April

How to create disk partitions in Linux?

Partitioning a disk allows you to create separate sections within the disk inorder to manage your data more efficiently. For example, in Windows you have C, D or E drives. There are various uses of partitioning a disk like:a) Allows to boot different OS from same diskb) Allocate separate partition to different usersc) Creating separate […]

09 February

Access Control List (ACL)

The standard Linux permissions are suitable for most situations but they have their own limitations. The standard permissions limit access to file owner, group owner and others. But, what-if we want to grant specific permission to another named user, other than the user-owner or another named group other than the group-owner. Access Control List (ACL) […]

05 February

Scheduling recurring tasks using crontab command

As a user if you want to schedule certain activities which should repeat themselves on their own at some time in the future i.e., you want to schedule recurring tasks then use the crontab command. In this post we will learn scheduling recurring tasks using crontab command There are different ways to use the crontab […]

24 January

How to Recover a Lost Root Password in Linux

At times we forget the root user password that we have set on our Linux machine. In this post, we will learn how to recover a lost root password in Linux. The procedure is most suitable of RedHat, Fedora and CentOS operating systems. Follow the below mentioned procedure: Step 1: Reboot the machine and stop […]

20 January

Loops(for while until) in Shell Scripting

Loops(for, while, until) in shell scripting are used to perform an operation multiple time. A loop is a portion of code that repeats (iterates) a set of commands till the loop control condition is true. For Loop in Shell Scripting The for loop in shell script has two syntax: Syntax 1: for variable in values […]