3658841 - SCC does not send the client certificate for Principal propagation.

In the ICM logs is possible to see the issue bellow where Cloud connector is not sending the system certificate : 

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[Thr 140115279902464] <<- SapSSLGetPeerInfo(sssl_hdl=7f6ef8024ba0)==SAP_O_K
             [Thr 140115279902464]     out: cert_len    = <no cert>
             [Thr 140115279902464]     out: csuite_name = "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256"
             [Thr 140115279902464] HttpIsReverseProxyTrustworthy: intermediary is NOT trusted 
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or

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There is external LB(like Azure Load Balancer) in front of SAP Web Dispatcher, in dev_webdisp following errors can be seen:

SSL Session Initialization
SapSSLSessionInit()
role=2 (SERVER), auth_type=1 (ASK_CLIENT_CERT)
...
Connection Info: role=Server, local=<WDP hostname>:<WDP port>, peer=<External LB IP>, protocol=HTTPS
...
Client certificate info: no certificate received
====

"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(SCC);
• SAP AS ABAP netweaver backend system.

HTTPS, no cert, trusted, allowlist, certificate, principal propagation, ELB-HealthChecker, mtls, CERTRULE, ICM, sample certificate, cert, PP, Principal proapgation, SSL, TLS , KBA , BC-MID-SCC , SAP Cloud Connector On-Demand/On-Premise Connectivity , BC-CST-WDP , Web Dispatcher , Problem