Capsule cannot be registered

Issue

• an attempt to add a Capsule to Satellite fails

• even if ports are opened and the Capsule is running on the host, satellite-installer ends up with an error:

  Unable to communicate with the Capsule: ERF12-2530 [ProxyAPI::ProxyException]: Unable to detect features ([RestClient::SSLCertificateNotVerified]: SSL_connect returned=1 errno=0 state=error: certificate verify failed (error number 1)) for Capsule https://someURL:9090/v2/features Please check the Capsule is configured and running on the host.  
  

• at /var/log/foreman-installer/capsule.log there is a following problem:

  'SSL_connect returned=1 errno=0 state=error: certificate verify failed (error number 1)) for Capsule https://someUrl:9090/v2/features'
  

NOTE: please keep in mind that in the above messages someUrl is your Capsule's FQDN