How To Fix /SAPAPO/CTM1808 - RFC connection not known

SAP Error Message - Details

• Message type: E = Error

• Message class: /SAPAPO/CTM1 -

• Message number: 808

• Message text: RFC connection not known

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

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Smart SAP Assistant

• What is the cause and solution for SAP error message /SAPAPO/CTM1808 - RFC connection not known ?

  The SAP error message /SAPAPO/CTM1808 RFC connection not known typically occurs in the context of SAP Advanced Planning and Optimization (APO) when the system is unable to establish a Remote Function Call (RFC) connection to the specified system. This can happen for various reasons, and here are some common causes, solutions, and related information:
  Causes:
  
  Incorrect RFC Destination: The RFC destination may not be correctly defined in the SAP system.
  Network Issues: There may be network connectivity issues between the systems.
  Authorization Issues: The user may not have the necessary authorizations to access the RFC destination.
  System Configuration: The target system may not be configured correctly to accept RFC calls.
  SAP Gateway Issues: The SAP Gateway service may not be running or may be misconfigured.
  
  Solutions:
  
  
  Check RFC Destination:
  
  Go to transaction SM59 in the SAP GUI.
  Verify that the RFC destination you are trying to use is correctly defined and active.
  Test the connection using the "Test Connection" button to ensure it is working.
  
  
  
  Network Connectivity:
  
  Ensure that there are no network issues preventing communication between the systems.
  Check firewall settings and network configurations.
  
  
  
  User Authorizations:
  
  Ensure that the user has the necessary authorizations to access the RFC destination.
  Check the user roles and profiles to confirm that they include the required permissions.
  
  
  
  System Configuration:
  
  Verify that the target system is configured to accept RFC calls.
  Check the instance profile and ensure that the necessary parameters for RFC are set correctly.
  
  
  
  SAP Gateway:
  
  Ensure that the SAP Gateway service is running on the target system.
  You can check the status of the gateway using transaction SMGW.
  
  
  
  Check Logs:
  
  Review the system logs for any additional error messages that may provide more context about the issue.
  Use transaction SM21 to check the system log and ST22 for dump analysis.
  
  
  
  Related Information:
  
  Documentation: Refer to SAP Help documentation for more details on RFC connections and troubleshooting.
  SAP Notes: Check for any relevant SAP Notes that may address specific issues related to RFC connections and the error message /SAPAPO/CTM1808.
  Support: If the issue persists, consider reaching out to SAP Support for further assistance.
  
  By following these steps, you should be able to identify and resolve the issue related to the RFC connection not being known in your SAP APO environment.