In this tutorial, we will show you how to set up Nginx High Availability cluster using Pacemaker on CentOS 7. To have an Nginx server that can operate continuously without failure for a long time, we need to configure the server with active-passive Nginx instances. Pacemaker is an open source cluster manager software that achieves maximum high availability of your services. It’s an advanced and scalable High Availability cluster manager distributed by ClusterLabs, it manages all cluster services and use the messaging and membership capabilities of the underlying cluster engine.