HAProxy is a load balancer TCP/HTTP , commonly used to improve the performance of web sites and services by spreading requests across multiple servers.[1] It is written in C[2] and has a reputation for being fast, efficient (in terms of processor and memory usage) and stable.[3]

HAProxy is used by a number of high-profile websites including Stack Overflow,[4] Reddit, Tumblr, and Twitter[5][6] and is used in the OpsWorks product from Amazon Web Services.[7]

HAProxy is free and open-source software subject to the terms of the GNU General Public License (GPL) version 2.

HAProxy stands for High Availability Proxy, and is a great TCP/HTTP load balancer. It distributes a workload across a set of servers to maximize performance and optimize resource usage.

A front-end application that relies on a database backend can easily over-saturate it with too many concurrent running connections. HAProxy provides queuing and throttling of connections towards one or more MySQL Servers and prevents a single server to become overloaded with too many requests.

All clients connect to the HAProxy instance, and the proxy forwards the connection to one of the available MySQL Servers based on the load-balancing scheme used.


RabbitMQ is open source message broker software (sometimes called message-oriented middleware) that implements the Advanced Message Queuing Protocol (AMQP). The RabbitMQ server is written in the Erlang programming language and is built on the Open Telecom Platform framework for clustering and failover. Client libraries to interface with the broker are available for all major programming languages.


wget -O /etc/yum.repos.d/epel-erlang.repo http://repos.fedorapeople.org/repos/peter/erlang/epel-erlang.repo
yum install erlang
rpm –import http://www.rabbitmq.com/rabbitmq-signing-key-public.asc
yum install rabbitmq-server-3.0.1-1.noarch.rpm
cd ..
cd downloads/

wget http://www.rabbitmq.com/releases/rabbitmq-server/v3.0.1/rabbitmq-server-3.0.1-1.noarch.rpm
yum install rabbitmq-server-3.0.1-1.noarch.rpm
/sbin/service rabbitmq-server start