General Troubleshooting

Ambari Server: Check /var/log/ambari-server/ambari-server.[log|out] for errors.
Ambari Agent: Check /var/log/ambari-agent/ambari-agent.[log|out] for errors.
Note that if Ambari Agent has any output in /var/log/ambari-agent/ambari-agent.out, it is indicative of a significant problem.

Services fail to start up

Nagios alerts don't show up in Ambari Web

Install Wizard fails during Install phase

Install Wizard failed with warning during Start/Test phase

Installing a new cluster on top of an existing cluster

When installing a Hadoop cluster via Ambari on hosts that already have Hadoop bits installed (including an existing cluster deployed via Ambari), perform the following:

HTTP error 400 – Bad Request – during REST call (POST, PUT, DELETE) to Ambari server

Ambari Server now expects an additional HTTP header called "X-Requested-By" for all non-GET calls. The value can be set to anything. For example:

curl -i -H 'X-Requested-By: mycompany' -X POST -d '{"Clusters": {"version": "HDP-2.0.6"}}' --user admin:admin


#Spaces in manager DN/Base DN causing login issues in Ambari

Note that there are some issues with Ambari current release 1.2.5 in case you have spaces in baseDN/managerDN. Please take a look at: The fix will be available in 1.4.1 release of Ambari. In case you are running into issues and cant get rid of spaces in the managerDN/baseDN - keep reading.

I have created a jar with the patch applied on top of branch-1.2.5. The jar is posted at

Download the above jar and follow the following steps for fixing the issue:

ambari-server stop
cp <downloaded_ambari_server_jar> /usr/lib/ambari-server/ambari-server-
ambari-server start

This should fix the issue with spaces in LDAP dn names.