High availability (HA) is a primary focus for all the framework or application available today. The application can be deployed either on-premise or over the cloud. There are many cloud service providers available today, such as Amazon AWS, Microsoft Azure, Google Cloud Platform, IBM Cloud, and so on. Achieving high availability using on-premise deployment has limited capability, for example even if we have multi node clusters available on-premise that have both HDFS storage and a processing engine up and running, it does not guarantee the required high level of availability in case any disaster happens. It requires also strict monitoring of the on-premise cluster in order to avoid any major loss and guaranteeing high availability.
In other words, cloud services provide more robust and reliable high availability features and there are multiple scenarios for considering what level of high availability we want to achieve it. Let us look into few conceptual scenarios...
