https://community.cloudera.com/t5/Support-Questions/namenode-is-not-formatted/m-p/183907#M146065 <P><A rel="user" href="https://community.cloudera.com/users/10486/simrank.html" nodeid="10486">@Simran Kaur</A>- How are you trying to restart the Namenodes? Using command line or using Ambari.</P><P>Also, as Romil has asked earlier, can you confirm if this HA or non HA cluster: </P><P>In HA cluster you will have two Namenodes running as Active and Standy Namenodes. They can switch states to become Active and Standy</P><P>In non HA environment there is only one Active Namenode. There is no switching of states. There is a Secondary Namenode, but that is mainly used for checkpointing purposes:</P><P><A href="http://blog.madhukaraphatak.com/secondary-namenode---what-it-really-do/" target="_blank">http://blog.madhukaraphatak.com/secondary-namenode---what-it-really-do/</A></P> Tue, 04 Apr 2017 05:58:26 GMT namaheshwari 2017-04-04T05:58:26Z