Unable to access Namenode UI after disabling Kerberos authentication

We get 401 authentication error after disabling Kerberos authentication sometimes, error is shown in below screenshot

Screenshot – Unable to access Namenode UI after disabling kerberos

unable to access namenode ui after disabling kerberos

This can break Ambari metrics as monitoring data wont be available over HTTP for Namenode/Resource manager or any other hadoop ecosystem UI.

How to resolve this issue?

Please check and verify if below property is set to true in core-site.xml

hadoop.http.authentication.simple.anonymous.allowed=true

Note – I have seen this issue most of the times because of above property being set to false.

Please also verify below property and modify if required.

hadoop.security.authentication=simple

Sometimes simple issue eats our valuable time! Posting this article to save your precious time 

Please comment if you face any issues or need any further help on this.

Happy Hadooping!!

by