How To Fix CACS_RTTS004 - RFC connection error for target system &1 - &2

SAP Error Message - Details

• Message type: E = Error

• Message class: CACS_RTTS - RTTS Services

• Message number: 004

• Message text: RFC connection error for target system &1 - &2

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.

Unfortunately, there isn't any extra information in this error notice.

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Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

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Smart SAP Assistant

• What is the cause and solution for SAP error message CACS_RTTS004 - RFC connection error for target system &1 - &2 ?

  The SAP error message CACS_RTTS004 indicates an RFC (Remote Function Call) connection error to a target system. This error typically arises when there is an issue with the connection settings or the target system itself. Here’s a breakdown of the potential causes, solutions, and related information:
  Causes:
  
  Network Issues: There may be network connectivity problems between the source and target systems.
  Incorrect RFC Destination: The RFC destination may not be configured correctly in the SAP system.
  Target System Down: The target SAP system may be down or not reachable.
  Authorization Issues: The user credentials used for the RFC connection may not have the necessary authorizations.
  Firewall Restrictions: Firewalls may be blocking the required ports for RFC communication.
  SAP Gateway Issues: The SAP Gateway service may not be running on the target system.
  
  Solutions:
  
  
  Check Network Connectivity:
  
  Use tools like ping or traceroute to verify that the source system can reach the target system.
  
  
  
  Verify RFC Destination Configuration:
  
  Go to transaction SM59 in the source system.
  Check the configuration of the RFC destination for the target system. Ensure that the connection type, target host, and system number are correct.
  Test the connection using the "Test Connection" button in SM59.
  
  
  
  Check Target System Status:
  
  Ensure that the target SAP system is up and running. You can check this by logging into the target system or checking its status through system monitoring tools.
  
  
  
  Review User Authorizations:
  
  Ensure that the user ID used for the RFC connection has the necessary authorizations in the target system.
  
  
  
  Firewall Configuration:
  
  Check if there are any firewall rules that might be blocking the RFC communication. Ensure that the required ports (usually 3200 for SAP) are open.
  
  
  
  SAP Gateway Service:
  
  Ensure that the SAP Gateway service is running on the target system. You can check this in transaction SMGW.
  
  
  
  Check Logs:
  
  Review the system logs in transaction SM21 for any additional error messages that might provide more context about the issue.
  
  
  
  Related Information:
  
  Transaction Codes:
  
  SM59: RFC Destinations
  SM21: System Log
  SMGW: Gateway Monitor
  
  
  SAP Notes: Check SAP Notes related to RFC connection issues for any known bugs or patches.
  Documentation: Refer to SAP Help documentation for detailed information on configuring RFC connections.
  
  By following these steps, you should be able to diagnose and resolve the CACS_RTTS004 RFC connection error. If the issue persists, consider reaching out to your SAP Basis team or SAP support for further assistance.