Hi David, Is the issue observed for a specific host? Can you try moving the concerned keytabs to another dir location. Then from Ambari UI perform the "Only regenerate keytabs for missing hosts and components". Ambari Agent logs should report this with below trace: Missing keytabs: Keytab: /etc/security/keytabs/smokeuser.headless.keytab Principal: The keytab file ideally gets modified by Ambari if the content is not matching with the keytabs in the Ambari cache. Hope this helps! ... View more