Application deployment architecture

Application architecture plays a crucial role to ensure High Availability of an application. An application whose components are deployed on a single machine is not highly available. When the machine reboots, the application is not available to its users. Similarly, depending on a single instance of a resource can become a single point of failure from a High Availability point of view. Each component of application should be designed in a manner that it can be deployed on multiple machines and redundancy should not be a bottleneck. Some software provides features related to High Availability and are not dependent on host operating systems or other third-party tools. SQL server availability groups is an example of such features.