The manual changeover feature is for use on systems that have Hot-Standby Pair or Triple-Standby server arrangements. It allows you to define which server is the Main server.
There are many possible reasons for needing to perform a manual changeover. Two common uses are:
- Switching a Standby server to Main as the original Main server is to be shut down for maintenance.
- Switching a Standby server to Main due to geographical factors. On a multi-server system, it is often easier to implement changes at the Main server. If the server at your current location is a Standby server, you can switch it to Main. This means you do not have to travel to the other server (which may be a considerable distance away).
There are two ways to perform a manual changeover:
- Using the Change Main Server Action in ViewX (see Manual Changeover without Server Shutdown). This is the recommended way of performing a manual changeover as it can be completed successfully without shutting down any of the servers.
- Shutting Down the Server that is Currently Main (see Manual Changeover with Server Shutdown). This forces a changeover as ClearSCADA performs an automatic changeover whenever ClearSCADA detects that the Main server has stopped (either intentionally or as a result of a failure).
Further Information