3722253 - Backend System Shows "Not Reachable" with "java.net.SocketTimeoutException: connect timed out" in SAP Cloud Connector

• An error occurs when communicating from BTP Integration Suite to S/4HANA or other application via SAP Cloud Connector. The error message shows:
  
  "org.apache.cxf.interceptor.Fault: Could not send Message., cause: org.apache.cxf.transport.http.HTTPException: HTTP response '503: Service Unavailable. There is no SAP Cloud Connector (SCC) connected to your subaccount matching the requested tunnel for subaccount 'subaccount id' and SCC location ID 'location_id'. Check the configuration on SCC and cloud side.'"
  
  
• HTTP/HTTPS connection under the specified subaccount id above is in "not reachable" state in the SAP Cloud Connector.
  
  
•  In the SCC UI (- SCC -> "Cloud to On-Premise" -> "Access Control" -> <select the related mapping> -> "Check availability" & "Show details", exception shows:
  
  "java.net.SocketTimeoutException: connect timed out (local port <port_number> to address <IP_ADDRESS_CLOUD_CONNECTOR> (source-host), remote port <port_number> to address <target_IP_address> (target_host))" 
  
  
• Further in the SCC log ( ljs_trace.log (<2.17)/ scc_core.trc (>=2.17)) following entries are there: 
  
  #INFO#com.sap.scc.rt#AccessControl connection checker#          #SccEndpointValidator failed to establish connection to HTTPS://<Hostname>:<Port>
  java.net.SocketTimeoutException: connect timed out (local port <port_number> to address <IP_ADDRESS_CLOUD_CONNECTOR> (source-host), remote port <port_number> to address <target_IP_address> (target_host)

* Image / Data in this KBA is from SAP internal systems, sample data, or demo systems. Any resemblance to real data is purely coincidental   

SAP Cloud Connector release independent.

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