The Linux Filesystem Explained

Have you ever wondered what all the folders on the root (/) directory of the Linux filesystem are for? Which file goes into which directories and why are they saved in those directories? On this post, we’ll check out each folder and what purpose or function they serve for the operating system itself. Continue reading “The Linux Filesystem Explained”

Comparing files using the diff command

The diff command outputs the differences between two files, line by line. For files that are identical it produces no output, for binary files only reports if they are different or not.

The set of differences produced by diff is often called a diff or patch, and this output can be used later on by the patch command to change other files. Continue reading “Comparing files using the diff command”

How To Tell If Your Linux Server Has Been Compromised

A server being compromised or hacked for the purpose of this guide is an unauthorized person or bot logging into the server in order to use it for their own, usually negative ends. However, the majority of compromised servers are carried out by bots i.e. automated attack programs, in-experienced attackers e.g. “script kiddies”, or dumb criminals. These sorts of attackers will abuse the server for all it’s worth whilst they have access to it and take few precautions to hide what they are doing.

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How to effectively use the GREP command

Grep is a very important & powerful Linux commands. It stands for ‘Global Regular Expression Print’ & is used for matching & printing a search pattern or a regular expression from a single or multiple text files. It will look for the pattern if the mentioned files & will than print the result on screen or to an output file.
In this tutorial, we are going to learn to use grep command with examples. Continue reading “How to effectively use the GREP command”

bash Tips and Tricks

I call these tips and tricks – “bash kung-fu”. You can save a lot of typing with these handy bash features.

bash, or the Bourne again shell, is the default shell in most Linux distributions. It has many features to enhance user-friendliness and productivity. Unfortunately, you can’t take advantage of those features unless you know they exist. So here are some bash tips and tricks that will help you with your everyday system admin tasks.
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Test internet speed from the Command-line

You probably have heard and tried using speedtest.net to test you computer or smartphone internet speed. If you have your own server or VPS you can also test internet speed connection from the command-line using the speedtest-cli utility. On this tutorial, I’ll show how to install and use speedtest-cli to test your internet speed.

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How to find out PID in Linux

Every Linux process has a process ID (PID) assigned to it.  It is a unique identification number that is automatically assigned to each process when it is created in an operating system. A process is a running instance of a program. In this tutorial we’ll look into ways on how to find the PID of process.

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Software RAID Recovery Tutorial

This tutorial will walk through the troubleshooting and recovery of a failed disk on a Software RAID setup. Especially mirroring the boot partition which is important when replacing disk and making sure the OS boots up properly after replacement.  This tutorial was done on Ubuntu 14.04 but should still work on other distributions such as RHEL and CentOS.

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