Puppet is a powerful configuration management and automation tool. Using the client server architecture of puppet, one can manage hundreds or even thousands of servers. Puppet saves lot of time for the system administrator. In this article I am going to give detailed steps to install and configure puppet Client/Server model in CentOS machines. Here I am using two VMs called puppet-server and puppet-client to demonstrate the puppet Client/Server setup.
Puppet package is provided in EPEL repository. We need to enable it to install puppet using YUM. On both puppet-server and puppet-client, install EPEL repository.
Note : I am using CentOS 5.7, so I am going to install EPEL for CentOS 5.
Update : Released 4.1 with cast/director/rating code update.
I am happy to announce the version 4 of IMDB movie fetcher. This release contains two new features and many bug fixes. This release adds colored output and “similar title” suggestions.
Arch Linux aur package is here . Download it and follow below steps
wget [--right click the above here link and copy paste the url here--]
tar zxvf imdbmoviefetcher.tar.gz
sudo pacman -U imdbmoviefetcher-4.0-1-any.pkg.tar.xz
Most of the time bash script need user input values to generate the data that is presented to user. There are many ways to accept user data in bash like reading data interactively, getting from parameters etc. But there are some situations where bash always need a set of data to generate the output. It will be a burden on the user to input the same data again and again, each time he executes the script. In that situations, storing the value in a configuration file will help. That file can be edited by user, if he requires to pass another set of data. You can see this concept in the BSD style init scripts, were boot parameters are stored in a centralized file like rc.conf.
Today I faced a problem with the script in which I was trying to produce colorized output based on the user preferences. It is unnecessary to ask user each time for his color preference. Instead of that he can just put the input in a configuration file and ask the script to read it. Another option is to hard code the color values in the script itself, but that will make it difficult for the user, if he want to change the color preference later. Continue reading
Linux uses framebuffer to show graphics in console. It is possible to see pictures or even video in console using framebuffer. In ubuntu the packages such as fbi, fbcat, mplayer etc can be used to see pictures, take screen shot and view video respectively. You need to be in any of the console by pressing CTRL+ALT+F1….6 to use these commands.
Fbi package to view pictures
The fbi package provides the framebuffer image viewer.
sudo apt-get install fbi
sudo fbi /path…/to/image
“High Availability” is the term coined with uptime. This is a method designed to increase the availability of services to the client, and thus provides more reliable servers/services for critical applications.
There are many enterprise grade open-source free applications available for implementing the high availability concept. The cluster suite provided with RHEL, CentOS is packed with bunch of kernel level and user level tools to implement high availability, also there are many other popular tools like heartbeat, pacemaker, drbd etc which helps to get reliable nodes and services.
The complexity of high availability tools makes it slightly difficult to understand and implement the technology. The aim of this article is to provide an overview of cluster/high availability applications. This will help you figure out the challenging task of how to best manage and provide high availability! Continue reading