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The Vim is a tool editor text. It is used as the most popular and powerful tool. In the context of Vim, it can operate in two modes: command mode and insert mode. The editor always starts in command mode. In the command mode, we can move through the text, search, replace, mark blocks and switch the editor to insert mode. The first, we will install Vim. On ubuntu sudo apt-get install vim On CentOS sudo yum install vim We use command vi file_name to open file in the Vim editor. We will start with some basic commands. Basic commands h to move the cursor to the left l to move it to the right k to move it to the up j to move it to the down G to move it to the begin of last line gg to move it to the begin of first line :n to move it to line n of the file Basic operations n dd will delete n lines starting from the current cursor position. u will undo. ctr + r will redo. n dw will delete n words starting from the current cursor position to right. n

In this tutorial, I show for you some concepts about heartbeat.  Heartbeat is a project from Linux-HA (Linux high available). The goal is t provide a High availability clustering solution for Linux. Heartbeat is the daemon which provides the cluster infrastructure. In order to be useful, heartbeat needs to be combined with a Cluster Resource Manager (CRM), which is the one in charge of starting and stopping the services (Web, DNS, Database, File servers and/or IP Addresss) to make them Highly Available. Through the years, Heartbeat has evolved and has different types of configurations: Heartbeat V1: This type of configuration uses the Version Cluster Resource Manager. This is also known as legacy Heartbeat. It allows us to configure two cluster node in active / passive or active / active configurations. Heartbeat V2: This type of configuration is related  to the use of the version 2 Cluster Resource Manager. It allows us to configure two or more nodes in active / passive or ac

Abstract: The Linux Virtual Sever Project (LVS) allows load balancing of networked services such as web or mail servers using Layer 4 Switching. It is very fast and allows such services to be scaled to service 10s or 100s of thousands of simultaneous connections. The purpose of this tutorial is demonstrate how to use various features of LVS to load balance Internet services, and how this can made highly avaiable using tools such as such as heartbeat and keepalived. It will also cover many advanced  topics which have been the subject of recent development including maintaining active connections in a highly available environment and using active feedback to better distribute load. Introduction The Linux Virtual Server (LVS) implements layers 4 Switching in the Linux Kernel. This allows TCP and UDP sessions to be to load balanced between multiple real server. Thus it provides a way to scale Internet services beyond a single host. HTTP and HTTPS traffic for the world wide web i