How To Fix /SMB/BB_INSTALLER421 - Host address changed to &1. Port unchanged.

SAP Error Message - Details

• Message type: E = Error

• Message class: /SMB/BB_INSTALLER -

• Message number: 421

• Message text: Host address changed to &1. Port unchanged.

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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Smart SAP Assistant

• What is the cause and solution for SAP error message /SMB/BB_INSTALLER421 - Host address changed to &1. Port unchanged. ?

  The SAP error message /SMB/BB_INSTALLER421 Host address changed to &1. Port unchanged. typically indicates that there has been a change in the host address of a system or service that the SAP system is trying to connect to, while the port number remains the same. This can occur in various scenarios, such as during system migrations, changes in network configurations, or updates to the system landscape.
  Cause:
  
  Network Configuration Changes: The host address may have been changed due to network reconfiguration, such as DNS changes or IP address reassignment.
  System Migration: If the SAP system has been migrated to a new server or environment, the host address may have changed.
  Configuration Errors: Incorrect settings in the SAP configuration files or in the system landscape can lead to this error.
  Load Balancer or Proxy Changes: If a load balancer or proxy is used, changes in its configuration can also lead to this error.
  
  Solution:
  
  Verify Host Address: Check the configuration settings in the SAP system to ensure that the host address is correct. This can typically be found in the transaction codes like SM59 (RFC Destinations) or SICF (HTTP Services).
  Update Configuration: If the host address has changed, update the relevant configuration settings in the SAP system to reflect the new address.
  Check Network Settings: Ensure that the network settings are correct and that the SAP system can resolve the new host address. You can use tools like ping or nslookup to verify connectivity.
  Review System Logs: Check the system logs for any additional error messages or warnings that may provide more context about the issue.
  Restart Services: After making changes, it may be necessary to restart the relevant SAP services or the entire SAP system to apply the new settings.
  Consult Documentation: Refer to SAP Notes or documentation related to the specific version of SAP you are using for any known issues or additional troubleshooting steps.
  
  Related Information:
  
  SAP Notes: Check the SAP Support Portal for any relevant SAP Notes that may address this specific error message or provide additional troubleshooting steps.
  System Landscape Directory (SLD): If you are using SLD, ensure that the system landscape is correctly configured and that the host addresses are up to date.
  Network Team: If the issue is related to network changes, it may be necessary to collaborate with your network team to ensure that all configurations are correct and that there are no connectivity issues.
  
  By following these steps, you should be able to identify the cause of the error and implement a solution to resolve it.