Failover is a process of shifting operations from an active data center to a standby data center, when the active data center fails.

During regular system operations, POM updates the database with the information such as campaigns, records that are being dialed, and agent states. The AlwaysOn feature of the MSSQL database maintains the database of all the replicated nodes in synchronization. When the data center fails because of a power outage, network outage, or natural calamity, all of the servers in that data center are not reachable for a long period of time. POM server in the failed data center loses connectivity to the database and fails to record the details of the calls into the database or records partial information to the database.

The failover process involves making standby data center as active and restarting the services. The POM server on the standby data center resumes operations from the information available in the database after it is active. There can also be a planned maintenance activity on an active data center because of which operations are shifted to the standby data center. The business operations occur from a standby data center until the maintenance on the active data center is completed.

The failover to the standby data center is categorized as Planned-Failover or Unplanned-Failover, based on whether the active data center fails abruptly while in production, or an outage is planned for maintenance.