## What changes were proposed in this pull request? In case there is a component that requires another service's headless keytab and there is no any component installed of that service the service level keytab regeneration did not work properly: the headless keytab was not regenerated.
## How was this patch tested? Latest unit test results in `ambari-server`: ``` [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESS [INFO] ------------------------------------------------------------------------ [INFO] Total time: 31:08 min [INFO] Finished at: 2018-09-21T15:17:50+02:00 [INFO] Final Memory: 170M/1245M [INFO] ------------------------------------------------------------------------ ``` Additionally the following E2E test steps were executed: 1. installed a secure cluster with `HDFS` and `TEZ` (+other dependencies) using `Ambari 2.7.1.0-163` 2. regenerated **all** keytabs (Kerberos / Regenerate Keytabs): no errors; **all** keytab files were updated on the disk 3. removed HDFS from `host 3` client where `Tez Client` was installed; please note that `Tez Client` is mapped to the headless keytab of HDFS at this point 4. regenerate keytabs for HDFS only: on `host 3` only Datanode's keytab was regenerated 5. built the new binary, replaced `ambari-server-x.jar` and restarted the server then repeated the last step: all relevant keytabs on all hosts were updates properly (including the HDFS headless keytab on `host 3`) [ Full content available at: https://github.com/apache/ambari/pull/2359 ] This message was relayed via gitbox.apache.org for [email protected]
