Reset Sum

 Resetting the Software Update Manager (SUM) in SAP Basis is a critical procedure, often needed when an update, upgrade, or conversion process gets stuck, fails, or needs to be restarted from an earlier point. It's not a trivial operation and requires careful attention to avoid system inconsistencies.

Here's an overview of how to reset SUM, along with important considerations:

Understanding SUM Phases and Reset Capability

SUM operations (upgrades, EHP installations, S/4HANA conversions, DMO) are divided into various phases.¹ The ability to "reset" SUM depends heavily on the current phase:

• Preparation Phases (typically before downtime): In the early phases (e.g., Extraction, Configuration, Checks, Preprocessing, often before the downtime has officially started), SUM usually offers more flexibility for resetting.
  • You might be able to use the "Back" button on the SUM UI to revert to a previous step.
  • A "Reset" option might be available in the "More" menu on the SUM UI.²
• Execution Phases (during downtime): Once the execution phases (especially those involving the actual system switch, data migration, or core component updates) have begun and the system is in downtime, a direct "reset" from the SUM UI becomes much more difficult, if not impossible, or highly risky. In such cases, you typically rely on:
  • Database backup: Restoring the entire system from a backup taken before the SUM process entered downtime.³ This is the safest and most recommended approach for critical failures during downtime.
  • Specific command-line resets: For certain severe inconsistencies or specific scenarios, SAP provides command-line options for SAPup (the backend process of SUM) to attempt a reset.

General Methods to Reset SUM

1. Reset from the SUM UI (Recommended when possible):

This is the cleanest way to reset if SUM allows it.

• Prerequisites:
  • The downtime has not yet started.
  • The SUM directory has not been cleaned up. (A cleanup deletes crucial logs and files, preventing a proper reset).
  • If using DMO (Database Migration Option), ensure the source database (AnyDB) is still available.⁴
• Procedure:
  1. Access the SUM UI: Log in to the SUM web user interface.
  2. Navigate to the "More" Menu: In the menu bar, look for "More" and select "Reset."
  3. Use the "Back" Button (if "Reset" is not active): If the "Reset" option is greyed out or unavailable, try clicking the "Back" button repeatedly until you reach a phase where "Reset" becomes active, or until you return to the "Welcome" dialog.
  4. Confirm Reset: Follow the prompts to confirm the reset.
  5. Cleanup: After a successful reset, SUM will typically prompt you to perform a cleanup of the SUM directory.⁵ This is mandatory after a reset to ensure a clean slate for a new attempt.

2. Reset from the Command Line (for specific phases or severe issues):

This method is used when the SUM UI is not accessible, or when specifically instructed by SAP Notes for a particular error in a preparation phase.

• Stop SUM: First, ensure all SUM processes (SAPup, SUMSUM, etc.) are stopped.⁶ You can usually do this by using the "Cancel" or "Exit" options in the SUM UI (if accessible) or by manually killing the processes at the OS level (use ps -ef | grep SAPup on Unix/Linux or Task Manager on Windows to identify and terminate processes).⁷
• Navigate to the SUM directory:
  • UNIX/Linux: cd <SUM directory>/abap/bin
  • Windows: cd <SUM directory>\abap\bin
• Execute the reset command:
  • For general preparation phase resets:
    • UNIX/Linux: ./SAPup reset prepare
    • Windows: .\SAPup.exe reset prepare
  • Note: Specific SAP Notes might provide different SAPup reset commands depending on the exact error and phase. Always refer to the relevant SAP Note for the precise command.
• Rename/Delete SUM Directory: After the command-line reset is confirmed successful, it's highly recommended to rename the existing SUM directory (e.g., SUM_OLD) and then unpack a fresh copy of SUM into a new directory for a clean start. This prevents any lingering inconsistencies from the previous run.

3. Using Report RSUPGRES (for specific inconsistencies, especially after improper resets):

In some cases, if a previous SUM run was not properly reset (e.g., by simply deleting the SUM directory without executing the reset commands), internal SAP tables might remain in an inconsistent state. SAP Note 1790486 (and similar ones) often recommend running report RSUPGRES to rectify such situations.⁸

• Procedure:
  1. Log in to the affected SAP system as user DDIC in client 000.
  2. Execute transaction SE38 or SA38.
  3. Run report RSUPGRES in the background.
  4. Do NOT stop the job manually. Let it complete.
  5. Ensure the /SUM/abap/log filesystem exists (if running in background).

4. Restoring from System Backup (for critical failures during downtime):

This is the ultimate recovery method when a SUM process fails irrevocably during the critical downtime phases.

• Prerequisites: You must have a valid, consistent backup of your entire SAP system (database and application servers) taken before you initiated the SUM process or at a defined safe point before the critical downtime.
• Procedure:
  1. Stop all SAP instances and database.
  2. Restore the database from the backup.
  3. Restore the application server file systems (if applicable, or simply delete and unpack a fresh kernel/executables if only database was affected).
  4. Start the SAP system.
  5. Delete the entire SUM directory.
  6. Unpack a fresh copy of SUM and start the entire update/upgrade process from scratch, ensuring all prerequisites are met.

Important Considerations for Resetting SUM:

• Always consult the relevant SAP Guide and SAP Notes: The specific steps for resetting SUM can vary slightly depending on the SUM version, the type of operation (upgrade, EHP, DMO), and the exact phase where the issue occurred. Always refer to the official SAP documentation (e.g., the "Resetting the Update" section in your SUM guide) and any specific SAP Notes related to the error you're facing.
• Backups are paramount: Before starting any SUM procedure, and especially before attempting a reset in critical phases, ensure you have a fresh, reliable backup of your entire SAP system.
• Understand the impact: A reset means reverting the system to an earlier state. Any changes made by SUM up to that point will be undone.
• Clean SUM directory: After a successful reset, it's best practice to delete the old SUM directory and unpack a fresh one to avoid any residual configuration or log file issues.
• Logging: Always review the SUM logs (SAPup.log, ELG files in the log directory) to understand why SUM stopped or failed before attempting a reset.⁹ This helps in addressing the root cause.
• DMO Specifics: If you are using SUM with the Database Migration Option (DMO), the reset procedures can have additional nuances, especially concerning the source and target databases. The DMO guide will provide specific instructions.

By following these guidelines and always referring to the official SAP documentation, you can effectively manage and reset SUM procedures in your SAP Basis operations.