Got "Bad Request This combination of host and port requires TLS" when access the link to CA WA ESP REST API

Products

• ESP Workload Automation

Issue/Introduction

We have started with ESP REST API STC with TLS configured. When access it thru web browser with HTTPS, we got error:
Bad Request This combination of host and port requires TLS.

Environment

Release : 12.0

Component : CA ESP WORKLOAD AUTOMATION

Cause

There are two possible causes:
#1 Sometimes even you enter HTTPS on web browser, it may still be resolved to HTTP. 

#2  If you want REST server to actually do the encryption. But if there is also AT-TLS rule for the same port, AT-TLS will encrypt already encrypted communication. 

Resolution

Solutions:
#1 Make sure HTTPS is used.

#2 Check if AT-TLS is set on MVS system; if yes, then the ESP REST API port should be excluded.