According to the Nutanix Support & Insights web search result3, shadow clones are vDisk copies that are created by the cluster when a vDisk is read by multiple VMs. Shadow clones are immutable copies of a vDisk that are stored in different nodes in the cluster, and are used to improve read performance and reduce network traffic. Shadow clones are automatically created and deleted by the cluster, based on the demand and availability of resources.

Explanation
The best way for the administrator to limit the amount of storage space that data stored in a single container can consume is to set an advertised capacity for the container. This will ensure that the data stored in the container doesn't exceed the set limit, and it will also help prevent any potential performance issues due to resource contention. Additionally, the administrator should consider thick provisioning the container, which will pre-allocate the amount of storage space that can be used by the container. This will help ensure that the data stored in the container doesn't exceed the advertised capacity.

According to the Nutanix Support & Insights web search result1, the administrator can change the frequency of checks and alerts for the System Non-Root Partition Usage in Prism Element by going to the Health Dashboard > Manage Checks > Schedule. The administrator can select the check name, such as disk_usage_check, and click on Edit Schedule. The administrator can then choose the desired frequency, such as every 15 minutes, every hour, or every day, and click on Save. This will change how often the check runs and alerts are generated.

when you create a custom alert policy, you can choose between two types of thresholds: Static Threshold and Behavioral Anomaly. Static Threshold allows you to set a fixed value for the metric that triggers the alert.
Behavioral Anomaly allows you to use machine learning to detect abnormal behavior based on historical data.
If you select Behavioral Anomaly as the threshold type, you cannot set a warning level for the alert. You can only set a critical level that indicates how much deviation from normal behavior is considered an anomaly3.
Therefore, the Alert warning if field is greyed out when you select Behavioral Anomaly.

According to the web search results, Prism Central is a multi-cluster manager that provides a single, centralized management interface for Nutanix environments12. One of the features of Prism Central is multi-cluster Single Sign On (SSO), which allows users to log in once and access multiple clusters without re-entering credentials3.