dragent

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dragent

dragent — Starts the database replication agent.

Synopsis

dragent master server-id[:port-num] replica server-id[:port-num] [statsinterval seconds] [username username-string password password-string]

Description

The dragent command starts the database replication agent and begins replicating the master database to the replica. See Chapter 12, Database Replication for more information about the database replication process.

Arguments

master server-id[:port-num]

Specifies the network address of one node from the master database cluster. The server-id can be an IP address or hostname. The port number to connect to is optional. By default, the replication agent uses three ports to connect to the master database server, starting with the default replication port (5555). If a different replication port was specified when the database server was started, you must specify that port number when starting the DR agent.

replica server-id[:port-num]

Specifies the network address of one node from the replica database cluster. The server-id can be an IP address or hostname. The port number to connect to is optional. By default, the replication agent uses the standard client port.

If security is enabled for the replica database, you must also specify a username and password as additional arguments. For example, the following command connects to the replica database antarctic using the username penguin and password wheretheylive:

$ dragent master arctic replica antarctic \
          username penguin password wheretheylive
statsinterval seconds

Specifies the frequency with which the agent reports statistics concerning the replication throughput. These statistics are useful in determining if replication is keeping up with the throughput from the master database.

Example

The following example starts database replication between the master database cluster that includes the node zeus and the replica database cluster that includes the node apollo. The replication agent uses the admin port to connect to apollo.

$ dragent master zeus replica apollo:21211