By using the deferred agent startup mode, you can configure OpenEdge Replication to allow database activity sooner than if you use the immediate agent startup mode. The deferred agent startup mode allows you to create a target database by doing an online backup of the source database. In contrast, the immediate agent startup mode requires that the source database be shut down while you perform the backup.
Note the following about deferred agent startup:
Schema updates are not allowed while the OpenEdge Replication server is performing synchronization. If schema updates are being performed when failure recovery synchronization begins, source database updates will block until failure recovery is complete.
Source database activity cannot continue without the agent(s) connected when synchronous replication is being used.
To use deferred agent startup, you must specify the value of the defer-agent-startup property for the OpenEdge Replication server in the [server] section of the source property file. If you set defer-agent-startup to a valid, non-zero time-out value, the source database can be active before the OpenEdge Replication server even contacts its configured agent(s). For more information on this property and its values, see the following:
The deferred agent startup mode configures the OpenEdge Replication server to do the following:
1. If the OpenEdge Replication server cannot connect to its configured agent(s) on the first connection attempt, it will go into deferred agent startup mode.
2. While in deferred agent startup mode, the OpenEdge Replication server will attempt to connect every five minutes until all agent(s) are connected or until the time-out specified as the value for the defer-agent-startup property expires.
If you do not want to wait the five minutes for the server to attempt connection to the agents, you can force agent connection using the connectagent command of the DSRUTIL utility. For more information, see DSRUTIL connectagent database qualifier.
To cancel defer-agent-startup, use the cancelDefer command of the DSRUTIL utility.
3. Once the server connects to the agent(s), startup, initialization, and synchronization are performed.
4. During the entire connection process, source database activity continues to occur but is halted briefly while the OpenEdge Replication server reinserts itself into normal database AI block processing.
Schema updates are not allowed while the OpenEdge Replication server is performing synchronization. If schema updates are being performed when failure recovery synchronization begins, source database updates will block until failure recovery is complete.