Apply maintenance to a shared configuration server farm
In a shared configuration environment, changes made to the shared file system are visible to all farm instances instantaneously. The changes might not be activated until a portal or application instance is restarted. Such changes include IBM WebSphere Application Server configuration changes. These changes are made to the shared configuration profile or updates to shared Java resources, like JAR files in a shared library or a redeployed application. Change the Farm Master. The Farm Master is the only server that should have write access to the shared file system.
Warning: Because we are sharing the file system and the database, most maintenance actions require a downtime with this type of farm configuration.
Apply maintenance requires the following general steps:
- Take the farm out of service.
- Shut down the Farm Workers.
- Apply the maintenance on the Farm Master.
- Start the Farm Workers.
We might have a business requirement to have only a minimal downtime for the environment. Use a setup called "two lines of production". In a farm, this setup results in a shadow setup of the farm. Both farm installations are used in an active or passive mode. While the active one is serving the request, the passive farm is available for maintenance. When maintenance is complete on the passive system, the roles of the system are switched. Then, maintenance can be applied to the second system. To keep customization data on both systems at the latest level, the Community and Customization domains are shared between systems.
- While all Farm Workers are mounted to Farm Image A, maintenance is applied to Farm Image B. Use Farm Master B in this instance.
- When maintenance is complete, stop each worker. Unmount Farm Image A and mount Farm Image B. Then, start the Worker with the new image.
- Finally, all Workers are running on Image B and maintenance is applied to the Farm Image A. Use Farm Master A.
As the Farm Workers are reused, the two lines of production setup require an additional Farm Master and more space on the shared file system.
Parent Maintain a portal farm