Ambari Workflow Manager view with kerberos fails to clear Oozie Service Check

[#1]

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.

oozie.service.ProxyUserService.proxyuser.<AMBARI_SERVER_PRINCIPAL_USER>.hosts=*
oozie.service.ProxyUserService.proxyuser.<AMBARI_SERVER_PRINCIPAL_USER>.groups=*

WORKAROUND / RESOLUTION :

Update below property in Oozie configs for Custom oozie-site.xml via Ambari UI and make the value to *:

oozie.service.ProxyUserService.proxyuser.<AMBARI_SERVER_PRINCIPAL_USER>.hosts=*
oozie.service.ProxyUserService.proxyuser.<AMBARI_SERVER_PRINCIPAL_USER>.groups=*

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".

More reference can be found HERE.