You are running a Hadoop cluster with NameNode on host mynamenode, a secondary NameNode
on host mysecondary and DataNodes.
Which best describes how you determine when the last checkpoint happened?

A.
Execute hdfs dfsadmin –report on the command line in and look at the Last Checkpoint
information.

B.
Execute hdfs dfsadmin –saveNameSpace on the command line which returns to you the last
checkpoint value in fstime file.

C.
Connect to the web UI of the Secondary NameNode (http://mysecondarynamenode:50090) and
look at the “Last Checkpoint” information

D.
Connect to the web UI of the NameNode (http://mynamenode:50070/) and look at the “Last
Checkpoint” information

Explanation:
Note: SecondaryNameNode: Is the worst name ever given to the module in the history of naming
conventions. It is only a check point server which actually gets a back up of the fsimage+edits files
from the namenode.
It basically serves as a checkpoint server.
But it does not come up online automatically when the namenode goes down!
Although the secondary namenode can be used to bring up the namenode in the worst case
scenario (manually) with some data loss.