How To Fix /IWBEP/CM_MGW_RT180 - If Max-Age is not initial then Do-Not-Cache-On-Client must be set to '-'

SAP Error Message - Details

• Message type: E = Error

• Message class: /IWBEP/CM_MGW_RT -

• Message number: 180

• Message text: If Max-Age is not initial then Do-Not-Cache-On-Client must be set to '-'

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /IWBEP/CM_MGW_RT180 - If Max-Age is not initial then Do-Not-Cache-On-Client must be set to '-' ?

  The SAP error message /IWBEP/CM_MGW_RT180 typically occurs in the context of SAP Gateway and OData services. This error indicates a conflict between the Max-Age HTTP header and the Do-Not-Cache-On-Client setting in the response.
  Cause:
  The error arises when the Max-Age header is set to a value greater than zero, which indicates that the response can be cached by the client for a specified duration. However, if the Do-Not-Cache-On-Client header is not set to '-', it creates a contradiction because the server is indicating that the response can be cached while also suggesting that it should not be cached.
  Solution:
  To resolve this error, you need to ensure that the Do-Not-Cache-On-Client header is set correctly based on the value of the Max-Age header. Here are the steps to fix the issue:
  
  
  Check the OData Service Configuration: 
  
  Go to the service definition in the SAP Gateway and check the settings for caching.
  Ensure that if Max-Age is set to a non-initial value, the Do-Not-Cache-On-Client should be set to '-'.
  
  
  
  Modify the Response Headers:
  
  If you are developing or customizing the OData service, you may need to adjust the code that sets these headers. 
  Ensure that when you set Max-Age, you also set Do-Not-Cache-On-Client to '-'.
  
  
  
  Testing:
  
  After making the changes, test the OData service again to ensure that the error no longer occurs.
  
  
  
  Related Information:
  
  Caching in OData Services: Understanding how caching works in OData services is crucial. The Max-Age header specifies the duration for which the response can be cached, while Do-Not-Cache-On-Client indicates whether the client should cache the response at all.
  SAP Gateway Documentation: Refer to the official SAP Gateway documentation for more details on configuring OData services and handling HTTP headers.
  Debugging: If you continue to face issues, consider using debugging tools to inspect the HTTP response headers being sent by the server to ensure they are set correctly.
  
  By following these steps, you should be able to resolve the error and ensure that your OData service behaves as expected regarding caching.