ERROR: Cannot set priority of namenode process

This error usually occurs when attempting to set the priority of the Namenode process using the 'renice' command and the user running the command does not have sufficient privileges to do so.

To resolve this issue, try running the command with root privileges by adding 'sudo' before the command. For example:

sudo renice -n <priority> -p <process_id>

Replace `<priority>` with the desired priority level and `<process_id>` with the process ID of the Namenode process.