PROBLEM : Ambari Workflow Manager view with kerberos fails to clear Oozie Service Check and errors out with proxy error in wfmanager-view.log.
ERROR :
11 May 2017 22:34:49,839 INFO [ambari-client-thread-26] [WORKFLOW_MANAGER 1.0.0 MyWFM] OozieDelegate:149 - Proxy request for url: [GET] http://space2.example.com:11000/oozie/v1/admin/configuration
11 May 2017 22:34:49,889 ERROR [ambari-client-thread-26] [WORKFLOW_MANAGER 1.0.0 MyWFM] OozieProxyImpersonator:456 - Error in GET proxyjava.lang.RuntimeException:
java.lang.NullPointerException
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1455)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1441)
at sun.net.www.protocol.http.HttpURLConnection.getHeaderField(HttpURLConnection.java:2979)
at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:489)
ROOT CAUSE : Missing below properties in custom oozie-site.xml.
Please restart the Oozie service and try accessing hive view from standalone view server.
Also make sure for Kerberized Ambari and HDP, in Ambari WORKFLOW_MANAGER view definition, you've WebHDFS Authorization as "auth=KERBEROS;proxyuser=<AMBARI_SERVER_PRINCIPAL_USER>" instead of "auth=SIMPLE".