Data Mover provides automatic failover support when multiple Data Mover servers are configured in a active-standby configuration. To use the automatic failover feature, two additional monitoring severs are required to monitor the active and standby components. The monitoring service uses SSH connections to monitor the primary (or active) components to see if services are running. If any of the main components are down, a failover sequence is initiated. A failover is initiated in the following scenarios:
- The active Data Mover daemon is unavailable
- The active Data Mover repository is unavailable
- All of the active Data Mover agents are unavailable
- The active ActiveMQ is unavailable.
When failover occurs, all active components are shut down and the standby components are restarted in active mode. The sync service is restarted in standby mode on the old active server. The monitoring service used to monitor the old active components is shut down and the monitoring service is started on the remote site to monitor the new active components.
See the Teradata® Data Mover Installation, Configuration, and Upgrade Guide for Customers, B035-4102 for information on the following DSA restrictions and related configurations:
- To enable failover for jobs using the DSA utility, preconfigure BAR NCs for the standby DSC environment (applicable regardless of database version).
- Source and target databases using version 16.00 or later can and should be preconfigured for the standby DSC environment.
- Source and target databases earlier than version 16.00 cannot be preconfigured if the active and standby Data Mover daemons are using the bundled DSC setup. When using multiple DSC environments to run jobs, you must reconfigure DSMAIN each time you want to run the same job after a Data Mover failover occurs.