SAP Knowledge Base Article - Preview

2338777 - Avoid having users accessing ICM and redirect to Web Dispatcher


If you just want to know how to redirect users to Web Dispatcher and avoid the users' directly in ICM, you can go to the Resolution section.

If a wrong redirect is made in the ICM side, it is possible that Web Dispatcher, in front of ICM, stop connecting to the ICM reporting errors like:

 *** WARNING => Failed to read group info for system <SID> (ABAP,HTTP): Internal ICM error(-1) [icrxx.c 3762]
 *** WARNING => Failed to read URL prefix info for system <SID> (ABAP,HTTP): Internal ICM error(-1) [icrxx.c 3762]

With a high trace level we see:

 NiICheckPendConnection: connection of hdl 704 to <dest IP>:<port> established
 NiIConnect: hdl 704 took local address <source IP>:<port>
 NiIConnect: state of hdl 704 NI_CONNECTED
 NiIWrite: hdl 704 sent data (wrt=93,pac=1,RAW_IO)
 NiIRead: hdl 704 recv would block (errno=EAGAIN)
 NiIRead: hdl 704 received data (rcd=376,pac=1,RAW_IO)
 IcrIHandleHTTPClientRequest: received response: len = 376
 ICT: IctIHttpOpenMessage: 120acf30 typ=2
 ICR: HTTP response error code = 307
 ICT: IctHttpCloseMessage( 120acf30 ) -> u=0 rc=0 
 NiICloseHandle: shutdown and close hdl 704/sock 90
 IcmConnClientRqFree: Connection 2/64302 closed
 IcmConnFreeContext: context 1 released
 IcrIHandleHTTPClientRequest: dest=<hostname>:<port>' URL='/sap/public/icf_info/icr_groups?version=2.2' -> -1
 HTR: decrement load factor: 80 -> 0 (d=80)
 ICR: IcrDetachFromServer -> 0
 ICR, system WMW: IcrIHandleHTTPClientRequest failed: Internal ICM error(-1), retry=3


In the browser we see error "503 Service not available" or even a message like  "server is redirecting the request for this address in a way that will never complete."

These are examples of wrong redirections made in ICM side that affect the Web Dispatcher behavior.



  • SAP NetWeaver Systems
  • SAP Web Dispatcher 


Webdispatcher, HTTP response modification, handler rewrite, header rewriting, Internet Communication Manager, icm/HTTP/mod_<xx>, icm/HTTP/mod_0, RegRedirectUrl, redirect connection to Web Dispatcher, avoid directly connections to ICM , KBA , BC-CST-WDP , Web Dispatcher , BC-CST-IC , Internet Communication Manager , Problem

About this page

This is a preview of a SAP Knowledge Base Article. Click more to access the full version on SAP for Me (Login required).

Search for additional results

Visit SAP Support Portal's SAP Notes and KBA Search.