Deploy AppEngine objects

Primary and Backup AppEngines can be deployed together or individually.

• When they are deployed together, regardless of which object is actually selected for deployment, the Primary always becomes the Active and the Backup becomes the Standby.

• When they are deployed individually, the first one deployed becomes the Active.

Hosted ApplicationObjects are always deployed to the Active AppEngine. When deploying the first of a redundant pair of AppEngines, you can cascade deploy all objects it hosts. This operation can be paired with deploying both the Primary and Backup AppEngines at the same time.

Important: If you deploy the Backup AppEngine first and then deploy hosted objects to that AppEngine, make sure the network communication to both target computers is good before deploying the Primary AppEngine. Otherwise, errors occur.

In the run-time environment, either the Primary or Backup AppEngine can become the Active or Standby depending upon failure conditions on either computer.