3509438 - SAP Cloud Connector - No tunnel channels are available to handle this request

When establishing an RFC connection between a BTP application (such as IBP or CPI) and an ABAP system through the SAP Cloud Connector, the following error was encountered in the SAP Cloud Connector trace (ljs_trace.log (<2.17)/scc_core.trc (>=2.17)): 

1. #WARN#com.sap.scc.protocol.rfc#forwarding-proxy-20-12#0x6e5ef785#Error during service channel tunnel processing in channel [id: 0xb5fc6aaf, L:/xxx.xx.xxx.xxx:3348 - R:/xxx.xx.xx.xxx:29822]: No tunnel channels are available to handle this request
2. #ERROR#com.sap.core.connectivity.tunnel.core.impl.processing.OutboundPacketProcessor#tunnel-client-70-4#0xxxxxxxxx#Internal error
   java.util.concurrent.RejectedExecutionException: Task com.sap.scc.protocol.rfc.RfcProtocolProcessorRunnable@xxxxxxx rejected from java.util.concurrent.ThreadPoolExecutor@xxxxxxxx[Running, pool size = 200, active threads = 191, queued tasks = 0, completed tasks = 170804247] 

"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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