Deployment Staging Modes

Deployment Staging Mode	Behavior
stage	The Administration Server first copies the deployment unit source files to the staging directories of target servers specified by the Staging Directory Name attribute. The target servers then deploy using their local copy of the deployment files.
nostage	The Administration Server does not copy deployment unit files. Instead, all servers deploy using the same physical copy of the deployment files, which must be directly accessible by the Administration Server and target servers. With nostage deployments of exploded archive directories, WebLogic Server automatically detects changes to a deployment's JSPs or Servlets and refreshes the deployment. (This behavior can be disabled if necessary.)
external_stage	The Administration Server does not copy deployment files. Instead, the Administrator must ensure that deployment files are distributed to the correct staging directory location before deployment (for example, by manually copying files prior to deployment). With external_stage deployments, the Administration Server requires a copy of the deployment files for validation purposes. Copies of the deployment files that reside in target servers' staging directories are not validated before deployment.