How To Fix APPLG409 - MUX: Slave proxy already exists in the synchronization job

SAP Error Message - Details

• Message type: E = Error

• Message class: APPLG - Application Graphics Messages (Graphic Proxy Framework)

• Message number: 409

• Message text: MUX: Slave proxy already exists in the synchronization job

What causes this issue?

A slave proxy is to be assigned to a synchronization job that
already exists.

System Response

The assignment is ignored. The other slave proxies are added to the
synchronization job.

How to fix this error?

Check the call method of the multiplexer.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message APPLG409 - MUX: Slave proxy already exists in the synchronization job ?

  The SAP error message APPLG409 with the description "MUX: Slave proxy already exists in the synchronization job" typically occurs in the context of SAP Landscape Management (LaMa) or when dealing with system replication and synchronization jobs. This error indicates that there is an attempt to add a slave proxy to a synchronization job, but a proxy with the same identifier already exists.
  Cause:
  
  Duplicate Configuration: The error is often caused by a configuration issue where a slave proxy has already been defined in the synchronization job.
  Job Misconfiguration: There may be a misconfiguration in the synchronization job settings, leading to the system trying to add a duplicate entry.
  System State: The system might be in a state where it has not properly released resources or cleaned up previous configurations, leading to conflicts.
  
  Solution:
  
  Check Existing Proxies: Review the synchronization job configuration to see if the slave proxy already exists. You can do this through the SAP GUI or the relevant management console.
  Remove Duplicate Entry: If you find that the slave proxy is indeed listed, you may need to remove the duplicate entry from the synchronization job.
  Reconfigure the Job: If necessary, reconfigure the synchronization job to ensure that it does not attempt to add the same slave proxy again.
  Restart Services: Sometimes, restarting the relevant services or the entire system can help clear up any temporary issues that might be causing the error.
  Check Logs: Review the logs for more detailed error messages or warnings that could provide additional context about the issue.
  
  Related Information:
  
  SAP Notes: Check SAP Notes for any specific patches or updates related to this error. SAP frequently releases notes that address known issues.
  Documentation: Refer to the official SAP documentation for Landscape Management or system replication for best practices and configuration guidelines.
  Support: If the issue persists after trying the above solutions, consider reaching out to SAP Support for further assistance. They can provide more tailored guidance based on your specific system configuration and version.
  
  By following these steps, you should be able to resolve the APPLG409 error and ensure that your synchronization job is configured correctly.