How To Fix WRF_UPGRADE_MSG018 - Unable to find suitable server for RFC: &1 &4

SAP Error Message - Details

• Message type: E = Error

• Message class: WRF_UPGRADE_MSG -

• Message number: 018

• Message text: Unable to find suitable server for RFC: &1 &4

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 WRF_UPGRADE_MSG018 - Unable to find suitable server for RFC: &1 &4 ?

  The SAP error message WRF_UPGRADE_MSG018 indicates that the system is unable to find a suitable server for a Remote Function Call (RFC). This can occur in various scenarios, particularly during system upgrades or when trying to connect to an external system.
  Causes:
  
  RFC Destination Configuration: The RFC destination may not be correctly configured in the SAP system. This could be due to incorrect parameters, missing entries, or misconfigured connection settings.
  Network Issues: There may be network connectivity issues between the SAP system and the target server. This could include firewall settings, network outages, or incorrect IP addresses.
  Server Availability: The target server may be down or not available for connections. This could be due to maintenance, server crashes, or other operational issues.
  Authorization Issues: The user credentials used for the RFC connection may not have the necessary authorizations to access the target server.
  SAP System Configuration: There may be issues with the SAP system configuration, such as missing or incorrect entries in the TMS (Transport Management System) or other related configurations.
  
  Solutions:
  
  
  Check RFC Destination:
  
  Go to transaction SM59 and verify the configuration of the RFC destination. Ensure that the connection parameters (like target host, system number, client, user, and password) are correct.
  Test the connection from SM59 to see if it is successful.
  
  
  
  Network Connectivity:
  
  Check the network connection between the SAP system and the target server. Use tools like ping or telnet to verify connectivity.
  Ensure that any firewalls or network security settings allow traffic between the two systems.
  
  
  
  Server Status:
  
  Verify that the target server is up and running. Check the server logs for any issues that might prevent it from accepting connections.
  
  
  
  Authorization Check:
  
  Ensure that the user credentials used for the RFC connection have the necessary authorizations. You can check this in transaction SU01.
  
  
  
  SAP Configuration:
  
  Review the SAP system configuration, especially in TMS, to ensure that all necessary configurations are in place and correct.
  
  
  
  Check Logs:
  
  Review the system logs (transaction SM21) and the developer trace (transaction ST22) for any additional error messages that might provide more context about the issue.
  
  
  
  Related Information:
  
  RFC (Remote Function Call): A protocol used in SAP systems to enable communication between different SAP systems or between SAP and non-SAP systems.
  SM59: Transaction code used to manage RFC destinations in SAP.
  TMS (Transport Management System): A tool used in SAP for managing transports between different systems in a landscape.
  Network Troubleshooting: Familiarity with basic network troubleshooting techniques can be helpful in diagnosing connectivity issues.
  
  If the issue persists after checking the above points, it may be necessary to involve your SAP Basis team or consult SAP support for further assistance.