Recommended service upgrade (RSU)

Recommended Service Upgrade (RSU) is a preventive service philosophy that applies to z/OS®. RSU is intended to reduce the volume of PTFs customers must apply for preventive maintenance and to reduce the chance of encountering a PTF in error (PE), resulting in a more stable system.

IBM® recommends that customers APPLY all RSU PTFs as preventive maintenance on their z/OS systems. However, customers must make the final decision as to what maintenance they will install.

The recommended service for the following products is tested in the Consolidated Service Test (CST) cycle:
  • z/OS
  • CICS® Transaction Server for OS/390®
  • Start of changeDb2® for z/OSEnd of change
  • IMS
  • Start of changeMQ for z/OSEnd of change
Recommended Service Upgrades, with an SMP/E SOURCEID of RSUyymm, are available:
  • Quarterly, with all PTFs that completed Consolidated Service Test (CST) testing during the prior quarter, including severity 1 through severity 4 APARs.
  • Start of changeMonthly, with high impact or pervasive (HIPER) PTFs, PTF-in-error (PE) PTFs, and other recommended PTFs (security or integrity fixes) that have been CST tested.End of change

For information about the latest recommended level of service, see Consolidated Service Test and the RSU.

Note: Although all CST-tested PTFs become RSU PTFs, not all RSU PTFs are tested in CST. Only the following systems or applications are included in the CST testing: z/OS, CICS, Db2, IMS, and MQSeries®.

Start of changeThe RSUyymm SOURCEIDs are provided in all z/OS product and PTF offerings, like Shopz and SMP/E RECEIVE ORDER.End of change