https://community.cloudera.com/t5/Support-Questions/1-How-can-I-view-the-history-of-switching-modes-standby/m-p/286328#M212377 <P>Hi&nbsp;</P><P>&nbsp;</P><P>Please find inline answers,</P><P>&nbsp;</P><P><SPAN>1) How can I view the history of switching modes (standby/active) in namenode service?</SPAN></P><P>&nbsp;</P><P>--&gt; You can check&nbsp;<SPAN>history of switching modes (standby/active) in namenode service</SPAN> in failover controler's log file.</P><P><BR /><SPAN>2) After how long of active namenode unavailability, standby becomes active?</SPAN></P><P>&nbsp;</P><P><SPAN>--&gt;&nbsp; It depends on how large your edits/fsimage files are to be synched.</SPAN></P><P>&nbsp;</P><P><SPAN>We recommend you to refer documents[1][2]</SPAN></P><P>&nbsp;</P><P><SPAN>[1]&nbsp;<A href="https://docs.cloudera.com/runtime/7.0.1/hdfs-overview/topics/hdfs-moving-highly-available-namenode-failover-controller-and-journalnode-roles-using-the-migrate-roles-wizard.html" target="_blank">https://docs.cloudera.com/runtime/7.0.1/hdfs-overview/topics/hdfs-moving-highly-available-namenode-failover-controller-and-journalnode-roles-using-the-migrate-roles-wizard.html</A></SPAN></P><P><SPAN>[2]&nbsp;<A href="https://stackoverflow.com/questions/27266267/namenode-ha-failover-time" target="_blank">https://stackoverflow.com/questions/27266267/namenode-ha-failover-time</A></SPAN></P> Wed, 25 Dec 2019 11:42:33 GMT senthh 2019-12-25T11:42:33Z