How To Fix WEBDYNPRO_RT021 - A request for server & was sent to server &. Note 1364846

SAP Error Message - Details

• Message type: E = Error

• Message class: WEBDYNPRO_RT - Message class of Web Dynpro runtime

• Message number: 021

• Message text: A request for server & was sent to server &. Note 1364846

What causes this issue?

A request, which was actually meant for server & has been sent to server
&.

System Response

The application has to be stopped here.

How to fix this error?

Check your network settings.
In particular, check that the proxy server, load balancer, or dispatcher
that is located between the browser and the back end is able to support
stateful SAP applications.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message WEBDYNPRO_RT021 - A request for server & was sent to server &. Note 1364846 ?

  Certainly! Here's a detailed explanation regarding the SAP error message WEBDYNPRO_RT021 and the related SAP Note 1364846.
  
  SAP Error Message: WEBDYNPRO_RT021
  Message Text:
  
  A request for server & was sent to server &.
  
  Cause
  This error typically occurs in SAP Web Dynpro applications when there is a mismatch or inconsistency in the server handling the request. Specifically:
  
  The Web Dynpro runtime expects a request to be processed by a particular server instance, but the request is routed to a different server.
  This can happen in load-balanced environments where the session affinity (sticky sessions) is not properly maintained.
  It may also occur if the Web Dispatcher or the load balancer is not configured correctly, causing requests to be sent to different application servers than expected.
  Another cause can be related to the Web Dynpro application’s internal state or session handling, where the server ID in the request does not match the server processing the request.
  
  
  Solution
  
  
  Check Load Balancer / Web Dispatcher Configuration:
  
  Ensure that session affinity (sticky sessions) is enabled so that all requests from a user session are routed to the same application server.
  Verify that the Web Dispatcher or load balancer is correctly configured to maintain session consistency.
  
  
  
  SAP Kernel and Web Dynpro Patches:
  
  Apply the latest SAP kernel patches and Web Dynpro component patches as recommended by SAP Notes.
  Sometimes, this error is caused by bugs fixed in newer kernel or Web Dynpro versions.
  
  
  
  Review SAP Note 1364846:
  
  SAP Note 1364846 specifically addresses this error message.
  The note provides detailed troubleshooting steps and corrections related to server routing and session handling.
  It may include patches or configuration recommendations.
  
  
  
  Check Web Dynpro Application Configuration:
  
  Verify that the Web Dynpro application is correctly deployed and configured.
  Check for any custom modifications that might affect session handling or server routing.
  
  
  
  SAP System Parameters:
  
  Review parameters related to Web Dynpro and HTTP session management.
  Parameters like icm/keep_alive_timeout, icm/server_port_*, and others might influence session persistence.
  
  
  
  
  Related Information
  
  
  SAP Note 1364846:
  
  This is the primary SAP Note related to this error. It explains the root cause and provides solutions or patches.
  
  You can access it via the SAP Support Portal by searching for Note 1364846.
  
  
  Load Balancer / Web Dispatcher Documentation:
  
  SAP documentation on configuring Web Dispatcher and load balancers for SAP NetWeaver Web Dynpro applications.
  
  
  SAP Community and Forums:
  
  Other users may have encountered similar issues; searching SAP Community forums with the error message can provide additional insights.
  
  
  
  Summary
  
  
  
  Aspect
  Details
  
  
  
  
  Error
  WEBDYNPRO_RT021: A request for server & was sent to server &
  
  
  Cause
  Request routed to a different server than expected due to load balancer/session issues.
  
  
  Solution
  Enable sticky sessions, check Web Dispatcher config, apply SAP Note 1364846, update kernel.
  
  
  Reference
  SAP Note 1364846, SAP Web Dispatcher docs, SAP Community forums
  
  
  
  
  If you have access to SAP Support, I recommend downloading and applying the instructions or patches from SAP Note 1364846 as the first step.
  
  If you want, I can help you with the exact steps to check your Web Dispatcher configuration or how to apply the SAP Note. Just let me know!