A load balancer is a device that distributes the traffic across a cluster of servers. In computing, load balancing improves the distribution of workloads across multiple computing resources, such as computers, a computer cluster, network links, central processing units, or disk drives.As a result, it improves responsiveness and increases the availability of applications. For load balancing, we need to install LAMP server on backend servers and HAProxy on the load balancer. HAProxy is a free, open source software that provides a high availability load balancer and proxy server for TCP and HTTP based applications that spread requests across multiple servers. Here we will make two backend servers and one load balancer. At two backend servers enter the following commands— $sudo apt-get install apache2 $sudo apt-get install mysql-server $sudo apt-get install php libapache2-mod-php php-mysql $sudo gedit /var/www/html/index.html (Mak...