2197601 - Web Dispatcher "-checkconfig" fails when SSL is used for the metadata exchange with the Message Server

The metadata exchange of the SAP Web Dispatcher was configured to use HTTPS when communicating with the Message Server, either by setting the parameter:

wdisp/server_info_protocol = https

Or by setting the arguments MSSPORT=<Message Server HTTPS port> and CONFIG_PROTOCOL=https to the wdisp/system_<xx> parameter(s).

The appropriate SSL trust was established by following the procedure documented on the SAP Community Wiki page - How to Configure SAP Web Dispatcher to Trust Backend System SSL Certificate

After that, executing the command sapwebdisp pf=<path to profile> -checkconfig, it raises one of the following errors:

Checking SAP Web Dispatcher Configuration
=========================================

maximum number of sockets supported on this host: 8192
Server info will be retrieved from host: <Message Server host>:<Message Server HTTPS port> with protocol:
 https
Checking connection to message server of system <SID>...ERROR: SapSSLSessionStart
failed SSSLERR_PEER_CERT_UNTRUSTED(-102)

Check ended with 1 errors, 0 warnings

------------------------------------------------------------------------------------------------------------------------

OR

Checking SAP Web Dispatcher Configuration
=========================================

maximum number of sockets supported on this host: 8192
Server info will be retrieved from host: <Message Server host>:<Message Server HTTPS port> with protocol:
 https
Checking connection to message server of system <SID>...OK
Retrieving server info from message server...ERROR: Connection to server
<Message Server host>:<Message Server HTTPS port> failed
ERROR: retrieving server info from message server failed: Network error (NI)(-8)

Check ended with 0 errors, 2 warnings

• Operating system independent
• Database independent
• SAP NetWeaver
• SAP Web Application Server for SAP S/4HANA
• ABAP Platform
• Client/Server Technology – SAP Web Dispatcher (WDP)
• SAP Web Dispatcher Release 742, 745 and 781

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