InfoSphere Replication Server

IBM® InfoSphere® Replication Server distributes, consolidates, and synchronizes data for high availability, high throughput, and business continuity.

Two types of replication, Q replication and SQL replication, support a broad range of business scenarios:

Q replication

A high-volume, low-latency replication solution that uses WebSphere® MQ message queues to transmit transactions between source and target databases or subsystems. A capture process reads the DB2® recovery log for changes to source tables and sends transactions as messages over queues, where they are read and applied to targets. Q replication offers the following advantages:

Minimum latency

Changes are sent as soon as they are committed at the source and read from the log.

High-volume throughput

The capture process can keep up with rapid changes at the source, and the multithreaded apply process can keep up with the speed of the communication channel.

Minimum network traffic

Messages are sent by using a compact format, and data-sending options enable you to transmit the minimum amount of data.

Asynchronous

The use of message queues enables the apply process to receive transactions without needing to connect to the source database or subsystem. If either of the replication programs is stopped, messages remain on queues to be processed whenever the program is ready. Because the messages are persistent, the source and target remain synchronized even if a system or device fails.

Q replication supports DB2 for z/OS® and DB2 for Linux, UNIX, and Windows as source platforms. Q replication supports the following target platforms: DB2 for z/OS, DB2 for Linux, UNIX, and Windows, Informix®, Microsoft SQL Server, Oracle, and Sybase.

SQL replication

SQL replication captures changes to source tables and views and uses staging tables to store committed transactional data. The changes are then read from the staging tables and replicated to corresponding target tables. SQL replication offers the following advantages:

Capture once

With staging tables, data can be captured and staged once for delivery to multiple targets, in different formats, and at different delivery intervals. Both tables and views are supported as sources.

Flexibility

You can replicate continuously, at intervals, or for one time only. You can also trigger replication with database events. You can replicate a subset of the table by excluding columns and filtering rows. You can also use expressions and other functions to transform data before it is applied.

Hub-and-spoke configurations

You can replicate data between a master data source and one or more replicas of the source. Changes that are made to the master source are propagated to the replicas, and changes that are made to the replicas are also propagated to the master source. Whenever a conflict occurs between the data that is sent from the master source and data this is sent from a replica, the data from the master source takes precedence.

SQL replication supports the following source and target platforms: DB2 for z/OS, DB2 for Linux, UNIX, and Windows, IBM DB2 for IBM i, Informix, Microsoft SQL Server, Oracle, and Sybase. In addition, SQL replication supports Teradata targets.