Open Systems Event Replicator Architecture - Replicating to a Relational Database

 

This diagram illustrates the Open Systems Event Replicator architecture.

 

Open_Systems_Event_Replicator_Overview.gif

 

In the diagram, the Event Replicator components are spread across three different servers, the recommended configuration. You can also install all components on a single Windows server (because the Replication Administrator must reside on Windows), or on two servers (the Replication Administrator must reside on Windows, the other components can reside on Windows, Linux or Unix servers).

 

The Open Systems Event Replicator consists of the following components:

 

  1. Adabas v6.1 (or above) for Open Systems

The Event Replicator real-time change data capture capability is only available in Adabas 6.1 and above for Open Systems and requires a special Adabas replication license. Contact Software AG for more information about obtaining the Open Systems Event Replicator license.

 

  1. Replication Administrator

The Event Replicator graphical user interface is written in C#.NET and can only run in a Windows environment. Using the Replication Administrator, you can define new replications in less than a minute.

 

  1. Event Producer (EP)

The Event Producer is a DLL (shared library) that is loaded by the Adabas nucleus. Every time a change is made to an Adabas database, the EP is notified of the change in real time. Transactions are grouped together and placed on the Message Queue, to be picked up by the Event Consumer.

 

  1. Message Queue (CNXMQ)

The CONNX Message Queue stores messages so the system can recover if communication is lost between components. If the Event Consumer or Controller components shut down for any reason (such as power outages or system reboots), the Message Queue ensures full recoverability when the components are brought back online again. Until the components are available, the EP persistently stores Adabas transactions that affect data content in the message queue for future retrieval.

 

  1. Controller

The Controller manages starting and stopping the Event Consumer. It also distributes the replication plan deployed by the Replication Administrator to the EP and the Event Consumer.

 

  1. Event Consumer (EC)

The Event Consumer is the heart of event replication.  The EC reads the transactions placed on the Message Queue by the EP, and using the appropriate ConnecX SQL Engine Adaptor, recreates the transaction on the target database.

 

  1. ConnecX SQL Engine

The EC uses the ConnecX SQL Engine  to perform "initial states."  An "initial state" moves all the data from a source Adabas file to a target table for the first time. Initial states may also be automatically initiated by the Event Replicator if an unrecoverable error occurs such as the Adabas database shutting down improperly.

 

  1. Designer Data Dictionary

The ConnecX SQL Engine  Event Replication Designer requires a data dictionary containing the Adabas files' SQL based definitions.

 

  1. ConnecX SQL Engine Target Adaptor

 In addition to the ConnecX SQL Engine , the Event Replicator requires adaptors for the target databases. The ConnecX SQL Engine has target adaptors for Oracle, SQL Server, DB2, Sybase, and Informix.