Zero Downtime Option for SAP S/4HANA

• Zero Downtime Option for SAP S/4HANA is an approach of Software Update Manager 2.0
• Apply feature and support package stack updates and release upgrades of SAP S/4HANA 2020 (or higher) without technical downtime
• The overall business downtime can be significantly reduced by using Zero Downtime Option
• Running the approach will require additional effort for project planning, impact analysis, and additional test runs
• The project requires an educated expert that has taken the respective SAP Learning Journey and successfully passed the related Knowledge Assessment 

The ultimate goal of Zero Downtime Option (ZDO) is to provide a solution to apply release upgrades, feature or support package stack updates for SAP S/4HANA without technical downtime. 

ZDO procedure:

• Business users work on the original system on release 1 which represents the source release.
• Meanwhile, the uptime processing of SUM has been started.
• At the end of uptime processing, SUM will rollover the end-users to the so-called bridge subsystem which still represents the source release..
• While the business continuous to work, the target release is finalized in parallel by SUM.
  
• During the maintenance procedure, transactional consistency is ensured.
• At the end of the maintenance event, the target release needs to be activated.
• The cut-over and activation of the target release includes the following steps:
  • Ramp-down release 1 which typically includes tasks like log off users, lock users, unschedule batch jobs, cleanup queues, and clean erroneous update processes.
  • Restart of all application servers by SUM. The database is not restarted.
  • Ramp-up of release 2 which typically includes tasks like import of transports, functional validation, unlock users, re-scheduled batch jobs.
• After the restart and ramp-up of the system, users will work on release 2 which represents the target release.