3661457 - PO system health checks fail post SSL configuration

• In Process Integration (PI) or Process Orchestration (PO) HTTPS has been recently configured as per HTTP and SSL | SAP Help Portal.
• The system has multiple Instances. 
• The system is using a Central SLD which is running on a separate host. 
• The system health checks fail and other vital health points fail, including: 
  • The Cache Connectivity Test.
  • SLD registrations are not as expected.
  • Full or Delta CPA cache updates fail.
  • Navigation around the Enterprise Services Repository (ESR) or Integration Builder.
• The error thrown will be similar to below:
  Connection to system REPOSITORY using application REPOSITORY lost. Detailed information: Sending request to https://<host>:<port?/rep/conntest/int? and receiving response ... FAILED! Message is: Unable to open SSL connection to host "<host>:<port>". Peer certificate rejected by ChainVerifier.
  Exception:
  Message: Unable to open SSL connection to host "<host>:<port>". Peer certificate rejected by ChainVerifier.
  Stacktrace:
  java.io.IOException: Unable to open SSL connection to host "<host>:<port>". Peer certificate rejected by ChainVerifier.

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SAP NetWeaver 7.5

esr login issue, id login issue, java.lang error, ssl connection error, peer certificate rejected, sap process orchestration, sap po, ssl configuration, trustedcas keystore, nwa ssl, sld certificates, integration builder, enterprise service repository. , KBA , BC-XI-CON-AFW-SEC , Security , BC-JAS-SEC , Security, User Management , Problem