What are the background process to monitor the HDFS and Namenode health check
you may check the process id of namenode through jps command on the master node and also datanode process on slave nodes and check for the process state using ps command.
Kindly use hdfs user superuser (hdfs) to run jps command. Also you may need to install jps binary if it's not already installed.
If you want to monitor you may schedule cron scripts to monitor the process so that it can give you alerts via email/sms.
by JPS command we can check which are hadoop service runing on cluster, i am looking what background/Daemon process in responsible for monitoring the Health check of HDFS
Following Demons : 0n hadoop cluster.
3 Daemons run on Master nodes:
NameNode – This daemon stores and maintains the metadata for HDFS.
Secondary NameNode – Performs housekeeping functions for the NameNode.
JobTracker/RM/YARN – Manages MapReduce jobs, distributes individual tasks to machines running the Task Tracker.
2 Daemons run on Slave nodes:
DataNode – Stores actual HDFS data blocks.
TaskTracker/Application Master – Responsible for instantiating and monitoring individual Map and Reduce tasks.