Usecase: Getting Error: java.net.UnknownHostException: Invalid Host:..... on Edureka VM as in the below screenshot.




From the above error, we can see that Resource Manager is not running and invalid host name. To overcome this, please check if the network adapter are connected and then run the below commands:


Command: sudo service hadoop-master stop

Command:  sudo service hadoop-master start

 

Command:  hadoop dfsadmin -safemode leave

 

Check if all the daemons are running fine with command: sudo jps and then try to run the Hadoop Commands.


Please feel free to revert if you need any further help.