Hello, In older versions of ambari, HDP 2.6.5 we've seen behavior that ambari uses the default cert/trustore pairs used by java instead of the values specified in Ambari UI.   Please try adding the cert to the default java cert store.   Also have you tried running ambari-server setup-security and specifying the cert path.   Also, on HDP 3.1 we've noticed that the node cert should be the only cert in the store for the correct cert to be extracted by Ambari. I.e. a store with all the node certs will not allow Ambari to extract the correct cert for the corresponding node.   HTH   Best, Lyubomir ... View more