Nagios is known as a comprehensive Network Performance Monitoring tool that comprises on manageable tools when it comes to Storage Management. You will probably find this website really helpful for best storage resource and management software, so just hae a look
https://appuals.com/the-5-best-storage-resource-monitoring-and-management-software/. It is exceptional for monitoring different features of storage such as the directory size, disk usage, and file size, among others. It utilizes a special Nagios 4 engine for better monitoring and immeasurable scalability.