Hadoop Installation – Data Node is not running problem

In this blog, I would like to list out points to try while facing problem of datanode not running in Hadoop cluster environment.

Basic things to checklist:

• Check for permission of files and folders.
• User and User group are properly assigned
• Check basic space requirement

Advanced Checklist:

• Stop all services
  bin/stop-yarn.sh bin/stop-dfs.sh

• Delete Hadoop Temp directory (hadoop.tmp.dir) as configured in core-site.xml
  rm -Rf /home/hduser/tmp/*
  

• Format the name node
  hadoop namenode -format
• Start hadoop Services
  bin/start-dfs.sh bin/start-yarn.sh
  If you still struggle to get datanode running, follow these
• Manually, start data node and check for errors
  bin/hadoop datanode
• By this point, you will get detailed error logs which you can solve depending upon the situation.

Do let me know if you find something else, I will update in the list so others can be benefited from this blog.

Happy Learning!