Dell only supports the use of time based retention settings with Milestone XProtect Corporate. To determine the capacity requirement for each recorder, calculate the number of cameras per recorder, the target bit rate per camera, and the retention time in days. Always consult with Milestone to determine an accurate capacity estimate.
All writes to the ECS cluster stop when the cluster capacity reaches 90% full. It is always recommended to plan for additional capacity as soon as you reach 75% of the cluster capacity.