During the deployment process, the DeploymentServer requires all essential agents in the target to be online and functional. The DeploymentServer identifies essential agents as follows:
Essential agents are responsible for deploying VFS assets to the target. If an essential agent goes offline during a deployment, the deployment fails.
Unessential agents are part of a target for the deployment of repository assets, but they are not responsible for VFS asset deployment. Deployment can succeed in their absence. However, if an unessential agent is offline during a deployment, additional maintenance is required when it is brought back online.
You must list unessential agents along with a target’s essential agents in your deployment topology so they can be notified at the appropriate times to flush repository caches and, if applicable, to switch data stores.
The property /atg/epub/DeploymentServer.allowMissingNonEssentialAgents determines whether unessential agents must be online and functional for deployments. Because offline agents can require additional post-deployment maintenance, the property allowMissingNonEssentialAgents is by default set to false. Consequently, like an essential agent, if an unessential agent goes offline during a deployment, the deployment fails.
You can permit unessential agents to be off-line during deployments by changing the property allowMissingNonEssentialAgents to true. If you do so, the agent is permitted to go offline at any time during the deployment, and you are notified when this occurs via a warning message written to the error log.
If an agent is offline when a deployment’s Activate Data phase begins, the DeploymentServer tries to reestablish contact before it performs any tasks that might affect it, such as flushing repository caches and switching data stores. If these contact attempts fail, after deployment is complete you might want to perform the following maintenance tasks on the agent:
Manually flush caches of its repositories.
If the agent is configured for deployments in switch mode, manually switch the agent’s switchable data stores so its current live stores are the same as those of all essential agents.
While this step synchronizes the agent with the others in the target, it is not required. A switch deployment always updates the newly inactive store (which is still used by the unessential agent) after updating and activating the newly live store. Furthermore, the
DeploymentServerautomatically synchronizes all online agents during the next deployment’s Activate Data phase.
