How To Fix CNV_CDMC_UCIA028 - Enter exactly one system with role R

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_CDMC_UCIA - CDMC Upgrade/Change Impact Analysis

• Message number: 028

• Message text: Enter exactly one system with role R

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_CDMC_UCIA028 - Enter exactly one system with role R ?

  The SAP error message CNV_CDMC_UCIA028 typically occurs during the execution of a conversion or migration process, particularly when using the SAP Conversion Tools or SAP S/4HANA Migration Cockpit. This error indicates that the system expects exactly one system to be defined with the role "R" (which usually stands for "Reference" or "Source") in the configuration.
  Cause:
  The error is caused by one of the following scenarios:
  
  Multiple Systems Defined: More than one system has been defined with the role "R" in the configuration.
  No System Defined: No system has been defined with the role "R".
  Incorrect Configuration: The configuration settings for the systems may not be set up correctly, leading to ambiguity in identifying the source system.
  
  Solution:
  To resolve this error, follow these steps:
  
  
  Check System Configuration:
  
  Go to the relevant transaction or configuration area where the systems are defined (e.g., transaction CNV_MBT or similar).
  Review the list of systems and their assigned roles.
  
  
  
  Ensure Exactly One System with Role "R":
  
  If there are multiple systems with the role "R", you need to either remove the extra entries or change their roles to something other than "R".
  If there is no system with the role "R", you need to add a system and assign it the role "R".
  
  
  
  Validate Configuration:
  
  After making changes, validate the configuration to ensure that it meets the requirements for the migration or conversion process.
  
  
  
  Re-run the Process:
  
  Once the configuration is corrected, re-run the migration or conversion process to see if the error persists.
  
  
  
  Related Information:
  
  Documentation: Refer to the official SAP documentation for the specific migration or conversion tool you are using. This documentation often provides detailed steps for configuration and troubleshooting.
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional context.
  Community Forums: Consider searching or posting in SAP community forums or SAP support channels for additional insights from other users who may have encountered the same issue.
  
  By ensuring that your system configuration adheres to the requirement of having exactly one system with the role "R", you should be able to resolve the CNV_CDMC_UCIA028 error.