No data for disk metrics

Why do I see 'No Data Available' for the metric Disk Busy and Idle Percentage in Linux monitoring?

The Linux monitoring agent uses the utility iostat to capture the disk idle and busy percentage. Please ensure the iostat utility is installed in your server. If not, please install it in the server and restart the monitoring agent service.

Please follow the steps below:
  1. Install the iostat utility
    1. For Debian:
      apt-get install iostat
    2. For CentOS, Fedora, RHEL:
      yum install iostat
  2. Execute the below command to check if the stats are seen in the Site24x7 web client:
    iostat -x -d ALL
  3. Restart the agent service:
    /etc/init.d/site24x7monagent restart