Mirror Replication Agent components

Mirror Replication Agent consists of a set of components that work together to propagate transactions from the mirror log devices to the Replication Server.

Figure 1-4 shows the flow of transaction data through a Mirror Replication Agent during normal (transaction replicating) operation.

Figure 1-4: Mirror Replication Agent transaction data flow

The flow of transaction data. Data flows from mirror log devices to the Mirror Replication Agent, which consists of a Log Transfer Manager, a Log Reader, and a Log Transfer Interface. The Log Reader passes the transaction data to the Log Transfer Interface, which outputs LTL commands to Replication Server.

The main Mirror Replication Agent components are:

Log Reader – reads the primary database transaction log on mirror log devices to retrieve transactions for replication, generates change-set data, and passes change sets to the Log Transfer Interface component.
Log Transfer Interface (LTI) – processes change-set data from the Log Reader, generates Log Transfer Language (LTL) commands, and sends the LTL commands and data to the Replication Server.
Log Transfer Manager (LTM) – manages all other components, coordinates their operations and interactions, and processes any errors reported by other components.