The best tips for Linux distributions including Ubuntu and CentOS.
Here is a simple script that utilizes xentop to monitor your Xen server. You can schedule this via cron to run every X minutes to track the load average and if gets too high, it will email you (be sure you change your-emailid to your actual email address) #!/bin/bash loadavg=`uptime | awk ‘{print $10}’` process=`nproc` … Read more
Here is powerful and simple use for the Linux find command – finding files or folders by one or more groups. Let’s get right onto the examples: Find files by group students find -type f . -group students Find folders/directories by group students find -type d . -group students Find files by groups student and teachers find -type … Read more
The find command in Linux/Unix is extremely powerful and can take some time to learn all of its uses. In previous articles, we have explained how to it to find files greater than or less than a certain size, find number of files in a folder, and finding the largest files on your computer. This article … Read more
While using the bzero() function you may have run into the message warning: incompatible implicit declaration of built-in function ‘bzero’. The solution for this common, annoying, message is straightforward. Simply include the header file <string.h> and the warning will go away! What is bzero? bzero() is a function in C and C++ programming languages, commonly used in … Read more
In a previous article, I showed you how to append a string to the end of file. Now I will show you how to insert a string to the beginning of a file in Linux. The solution is not as obvious as the former, but I will show you a quick and easy way using … Read more
If you are looking for a quick and easily solution to changing your Linux passwd from a script, you have come to the right place. As you already know, the passwd command prompts the user to enter the desired password as well as a confirmation, but I have a solution that will change the password … Read more
This article will go through some basic examples on how to list files above or below a certain size in Linux using the find command. There are many use cases for running queries like this, for instance finding small files on your hard drive or finding very large files. So, lets get started with some examples. Using find … Read more
I am running Ubuntu 11.04 and was trying to install the Java OpenJDK 6.0 (and 7.0) on my system but I received the following error: Unable to fetch some archives, maybe run apt-get update or try with –fix-missing? I tried installing several different Java packages but all of them failed with the same error. Finally, … Read more
Have you tried doing yum install ruby in CentOS 5.5? If you have the default repositories configured, you will notice that it installs the ancient Ruby 1.8.5. Not ready to move up to Ruby 1.9, but would like to install Ruby 1.8.7 – well here is how to do it! Install Ruby 1.8.7 on CentOS … Read more
When you login (via SSH or other method), to a Linux box, you will see a Welcome message that displays your Last Login time and date as well as other general information regarding the system. Here is an example: Linux sp-ubuntu 2.6.35-24-generic #42-Ubuntu SMP Thu Dec 2 01:41:57 UTC 2010 i686 GNU/Linux Ubuntu 10.10 Welcome … Read more
In the vast landscape of digital content management, the need to convert PDF files to text is a common task for professionals, students, and casual users alike. PDFs are widely used for their portability and consistency across different platforms but aren’t as easy to edit or search as plain text files. Fortunately, for Linux users, … Read more
Do you need an ultra fast way to create a large number of files in Linux? Perhaps, you are doing some load testing for an application and you need to create 1000 or even 1,000,000 files in the matter of seconds. Well, here is how to do it! There are two parts to creating these … Read more
This article will show you how to use the head command in Linux. head is used to print out the beginning of a file. For example, this is useful when you have a giant text file and you want to preview the contents without attempting to open the entire file. Here are some common examples … Read more
This article will show you how to add a network printer on a Ubuntu 9.10 system. Let’s go ahead and get started… Navigate to System –> Administration –> Printing Then choose Server –> New –> Printer from the Printer configuration window The New Printer wizard will be displayed. Here you can add either local or … Read more
Linux is a highly efficient and flexible operating system, but there are times when processes can misbehave, slow down the system, or consume excessive resources. In such cases, it may be necessary to terminate one, multiple, or even all processes. This guide provides a detailed explanation of how to kill all processes in Linux using … Read more
This article will show you how to change your monitor resolution in Ubuntu 9.10. Most of us are long-time Windows users and we are very used to the interface and how to do a simple task like this. But for Linux newbies, it can get frustrating to navigate all the menu options to find the … Read more
This article will show you are to disable UAC (User Access Controls) aka those pesky popup dialogs where you must enter your password in Ubuntu Linux! As many of you know, this feature was implemented in Windows Vista but went horribly wrong and is the reason it has been removed in Windows 7. Linux, which … Read more
The Secure Shell Daemon (SSHD) is a critical service for Linux users and administrators, providing a secure method to access remote machines over an insecure network. This service encrypts the connection between the client and the server, ensuring that sensitive information, such as passwords and user data, is transmitted securely. This comprehensive guide will walk … Read more
This article will introduce you to the diff command on Linux which is used to compare two files and display the “differences” between the two. I will also provide you with a Bash shell script to compare two files and simply output if they are the same or not. Lets begin with the basic usage … Read more
This article will explain how to generate a MD5 Checksum on a file or list of files on Linux and how to validate a file against a known checksum. We’ll give you easy-to-follow examples as well as explanations. Let’s get started! What is a MD5 Checksum? The MD5 checksum is a widely used cryptographic hash … Read more
In the digital world, file compression is a fundamental technique to reduce file sizes for storage efficiency and faster transmission. Among various compression formats, the .tar.bz2 format stands out for its high compression ratio, especially useful for packaging a collection of files or directories into a single file. This guide delves into the process of … Read more
FTP (File Transfer Protocol) servers are a fundamental aspect of data exchange in networked systems. Particularly on Linux, an open-source platform known for its robustness and adaptability, FTP servers serve as powerful tools for managing and transferring files across network connections. From software development to web hosting, FTP servers allow users to upload, download, and … Read more
Appending data to files is a common task in Linux, whether you’re updating logs, adding configuration settings, or combining file contents. Linux provides several straightforward methods to append text or other data to an existing file. This guide will cover different tools and commands you can use for this purpose. Using the >> Operator for … Read more
This guide will take you through the basics of RPM and show you how to install it on different Linux server distributions: Ubuntu, CentOS, Fedora, and Red Hat Enterprise Linux (RHEL). In the world of Linux, mastering the art of installing, upgrading, and removing software packages is crucial. These tasks are generally handled by what’s … Read more
This article will show you to how to list of all installed RPM packages on Linux distributions like Ubuntu, CentOS, RHEL, and Fedora. We’ll show you how to solve this using the rpm and dpkg commands. RPM (Red Hat Package Manager) is used by distributions such as CentOS, RHEL, and Fedora for package management. Ubuntu, … Read more