This host-level alert is triggered if the NameNode process cannot be confirmed to be
up and listening on the network for the configured critical threshold, given in seconds.
It uses the Nagios check_tcp
The NameNode process is down on the HDFS master host
The NameNode process is up and running but not listening on the correct network port (default 8201)
The Nagios server cannot connect to the HDFS master through the network.
Check for any errors in the logs (
/var/log/hadoop/hdfs/)and restart the NameNode host/process using the HMC Manage Services tab.Run the
netstat-tuplpncommand to check if the NameNode process is bound to the correct network portUse
pingto check the network connection between the Nagios server and the NameNode
