Log on your ambari-server bring it down and reset it $ ambari-server stop $ ambari-server reset
If you are using postgresql – installed and configured by ambari server, you should be able to restart. If you are using MySQL or Oracle, you will need to drop / re-create the database manually. $ ambari-server setup …. Good luck, Olivier From: Kaliyug Antagonist Reply-To: "user@ambari.apache.org<mailto:user@ambari.apache.org>" Date: Thursday, 6 August 2015 10:07 To: "user@ambari.apache.org<mailto:user@ambari.apache.org>" Subject: Clean un-installation via Ambari I had installed HDP-2.2.4.2-2 using Ambari Version 2.0.0. There have been several issues in the cluster due to misconfiguration in the datanode directories and so on. Now I get several alerts and any MR that I execute fails with an error like this : 15/06/01 13:53:44 INFO mapreduce.Job: Job job_1431689151537_0003 running in uber mode : false 15/06/01 13:53:44 INFO mapreduce.Job: map 0% reduce 0% 15/06/01 13:53:47 INFO mapreduce.Job: Task Id : attempt_1431689151537_0003_m_000000_1000, Status : FAILED java.io.FileNotFoundException: File /opt/dev/sdb/hadoop/yarn/local/filecache does not exist 15/06/01 13:53:51 INFO mapreduce.Job: Task Id : attempt_1431689151537_0003_m_000000_1001, Status : FAILED java.io.FileNotFoundException: File /opt/dev/sdd/hadoop/yarn/local/filecache does not exist 15/06/01 13:53:55 INFO mapreduce.Job: Task Id : attempt_1431689151537_0003_m_000000_1002, Status : FAILED java.io.FileNotFoundException: File /opt/dev/sdh/hadoop/yarn/local/filecache does not exist I wish to clean un install the cluster and reinstall it, it is ok even if Ambari needs to be uninstalled and reinstalled. How can I do it ?