Virtual switching is the process of testing that your production environment applications can access the objects they need and run on a backup node in a MIMIX environment without shutting down the applications or stopping MIMIX.
The purpose and scope of a virtual switch test differ from a planned switch test in the following ways:
A virtual switch test does not switch anything. MIMIX support for virtual switching sets up your MIMIX environment to allow a designated backup node to be used for testing while the production environment and MIMIX remain active. Only apply processes and access path maintenance (if configured) for data groups that currently use the test node as their backup node are ended. Other replication processes remain active, so production node transactions are processed, sent to the target node, and remain queued for apply processes until testing is complete. While you are testing that the applications can run on the designated test node, MIMIX tracks any changes made to replicated objects on that node. After you indicate that testing is complete, MIMIX reverts those changes, restarts the apply processes, and returns the node to normal operation.
A planned switch test is a complete planned switch for the purpose of verifying that all aspects of the switch perform as expected. A planned switch test shuts down the production environment and MIMIX replication, switches the production environment to the backup node (which becomes the new primary node), and restarts MIMIX replication with the new primary node as its source. A second planned switch is required to return the production environment to the original primary node.
Virtual switching is an excellent way to identify and correct problems that could otherwise inhibit or prevent applications from starting on the new primary node during a planned or unplanned switch. However, a virtual switch does not replace the need to perform a planned switch test. Some applications are not suitable for virtual switching. Also, a virtual switch cannot test some aspects of your environment, such as IP impersonation, and does not allow you to validate that the MIMIX configuration operates as expected from the test node.