Configuring a clustered environment for high availability

Creating a cluster of machines, and using cluster managing software to balance work load on those machines is one strategy for designing a highly available solution. If you install IBM® Db2® server on one or several of the machines in a cluster, you must configure the cluster manager to properly react to failures that affect the database or databases. Also, you must configure the database manager instances to work properly in the clustered environment.

About this task

Configuring and administering the database instances and the cluster manager manually is complex, time consuming, and prone to error. The Db2 High Availability Feature provides infrastructure for enabling the database manager to communicate with your cluster manager when instance configuration changes, such as stopping a database manager instance, require cluster changes.
Note: If you are using an AIX® system, consider enabling the system error log (syslog) to capture relevant messages from Tivoli® SA MP and RSCT subsystems and from the Db2 automation scripts. For more information, see the Related links.

Procedure

  1. Install cluster managing software.
    Note: Starting in Db2 version 11.5.5, Pacemaker as an alternate cluster manager is available for automated failover to HADR standby on Linux for on-premise and non-containerized cloud deployments. If you are on Db2 version 11.5.4, Pacemaker is still a Technical Preview. For details, see Integrated solution using Pacemaker.

    SA MP is integrated with Db2 Enterprise Server Edition, Db2 Advanced Enterprise Server Edition, Db2 Workgroup Server Edition, Db2 Connect Enterprise Edition, and Db2 Connect Application Server Edition on AIX and Linux operating systems. On Windows operating systems, SA MP is bundled with all of these Db2 database products and features, but it is not integrated with the Db2 installer.

  2. Configure Db2 database manager instances for your cluster manager, and configure your cluster manager for Db2 server.

    Db2 high availability instance configuration utility (db2haicu) is a text-based utility that you can use to configure and administer your highly available databases in a clustered environment.

  3. Over time, as your database needs change and you need to modify your database configuration within the clustered environment, continue to keep the database manager instance configuration and the cluster manager configuration synchronized.