In previous tutorials we introduced Ansible and we discussed Ansible loops. This time we learn the basic usage of some modules we can use inside playbooks to perform some of the most common system administration operations.
scripting
Introduction to YAML with Examples
YAML is a data serialization language. The name itself is a recursive acronym which stands for YAML Ain’t Markup Language. It is specifically designed to be human-friendly, easy to read and write, to represent settings and data structures and to work well with modern programming languages.
Exit code 127 error status in Bash script
Are you receiving a exit code 127 error when trying to execute a Bash script? In this tutorial, we’ll explain what causes this “command not found” error and show you how to fix it.
How to manipulate Excel spreadsheets with Python and openpyxl
Python is a general purpose programming language that needs no presentations. It was originally written by Guido Van Rossum, and saw its first release in the year 1991. At the moment of writing, the latest stable version of the language is 3.10. In this tutorial we see how to use it together with the openpyxl library to manipulate Excel spreadsheets.
Count lines of code with cloc
It can be difficult to count the number of lines of code that comprises a certain program, since simply viewing the source code will include comments, whitespace, etc. On Linux systems, the cloc command can be used to count lines of code in one or multiple files, and even sort results by programming language.
Bash countdown timer
Using a bit of Bash scripting, it’s possible to create a countdown timer in Linux. This will allow you to countdown in seconds, minutes, or to some future date.
Extract email from text file
The Linux command line has many tools that we can use to extract information from text files. In this tutorial, we’ll use a few different methods to extract email addresses from a text file on Linux.
C++ code on how to read characters from a file
This tutorial will show you a small example of C++ code on how to read a characters from a file, as well as to count the number lines that any particular file consist of. We will be creating the script and compiling the C++ on a Linux system. All distros will work the same, provided you have the G++ compiler installed, which we will cover as well.
logrotate command in Linux with examples
In Linux, many applications and system services will store log files. These log files give a Linux administrator insight into how their system is performing, and are invaluable when troubleshooting issues. However, log files can get unwieldy very quickly. For example, if your web server software logs every visit to your website, and you get thousands of viewers per day, there will be way too much information to feasibly squeeze into one text file.
usermod command in Linux with examples
The usermod command in Linux is used to modify user accounts. In particular, it’s used for changing various attributes for accounts that are already created, since a separate command is used when creating a brand new account on Linux.
Cat command in Linux with examples
The cat command in Linux is our primary tool for viewing the contents of text files on Linux systems. When using or administrating a Linux system, you are usually confronted with a command line. There are no graphical aids such as mouse or windows to help you navigate through directories or edit files.