An administrator receives the alert:“Container on cluster running out of storage in approximately 1 day.

Nutanix documentation explains that Reserved Capacity for a storage container allocates a guaranteed amount of physical space exclusively for that container. The internal description is:

“Reserved Capacity is space carved out from the storage pool for guaranteed use by a container. When a container’s reserved allocation approaches exhaustion, alerts are raised even if the overall cluster has ample free space.”

This means that although the physical cluster capacity may be sufficient, the container itself may hit its reserved limit, triggering an out-of-space forecast. Advertised Capacity determines an upper usage limit but does not produce this behavior. Replication Factor affects total usage but cannot explain container-only exhaustion when the cluster is fine. Compression levels influence data reduction but not capacity alerting mechanisms.

Thus, an oversized Reserved Capacity value is responsible for the alert.