Let’s start with the need for a sudoers file! — Introduction: We take the sudo and su command for granted. We use it so often to get root privileges but what happens under the hood is interesting! When we execute sudo on the command, the OS checks a file to see if we have the privileges for the upgrade. …

All about the use-cases for IP commands — Introduction: As a person with a Computer Networking background, IP utility is one of the most common tools I use on a day to day basis. This utility is crucial in troubleshooting routing issues. It also plays a significant role in understanding the packet traversal from source to destination, specifically answering…

A brief overview of various types of links — Introduction: Creating links is a common practice in a Linux based Operating system. They make it easy to access a specific file from multiple locations on the file system. I believe that soft links are more commonly used than hard links. The difference between the two types of links will be…

All you need to know about SetUID, SetGID and Sticky Bit — Introduction: File Permissions are a crucial entity in the Linux File System. They decide if a specific user can create, edit, delete, or execute a file. Understanding basic file permissions in Linux and types of ownership (user, group, other) is important to understand the concepts of this article better. …

All about inotifywait and iwatch utilities — Introduction: I have recently come across inotifywait and iwatch, the real-time file monitoring tools. I am familiar with inodes to some extent but didn’t come across inotify before, until recently. Both of these tools are very powerful and are of high value when it comes to File System Monitoring. …

A guide to Netcat — TCP/IP Swiss Army knife — Introduction: Netcat is regarded as TCP/IP Swiss Army Knife. It is a command-line utility that is so simple yet powerful and can perform operations related to Transmission Control Protocol (TCP), User Data Protocol (UDP). …

How to run Network Utilities as an Unprivileged User? — Introduction: We come across situations where a specific set of binaries can only be run as a privileged user. There can be use-cases where a user or a group of users, without root privileges, have to run these binaries. One example is the tcpdump network utility. tcpdump can only be run…

All about Curl and its options! — Introduction: cURL ( stands for Client URL) is a software that provides a library libcurl and command-line tool curl. The features and support that it provides are way overwhelming, there are so many options that can be passed to it, sometimes you are just lost in the man page. This article…

Common Scenario for Network Connection Timed out Error — Introduction and Background: You are in trouble if your HTTP server greets you with a 599:Network Connection Timed out Error. The first thing to check is if the server is reachable and you can SSH into it. Then comes to the rescue, the log file of the server. …