What-If Analysis feature in Aria Operations not functioning as expected - discrepancy in the estimated host count, particularly regarding storage analysis.

Products

• VCF Operations/Automation (formerly VMware Aria Suite)

Issue/Introduction

While using What-If Analysis feature in Aria Operations, it is not functioning as expected. Specifically, there is a significant discrepancy in the estimated host count, particularly regarding storage analysis.

 

For example, a workload with an overall requirement of 280 TB results in a host recommendation for only around 150 TB of storage.

Environment

Aria Operations 8.18.x

Cause

This issue occurs during the projection calculation for a workload in a migration scenario. The system is incorrectly calculating projections based on metrics from the capacity definitions of the VMs.  

For accurate Disk Space projections in this "What-if" scenario, the calculation relies on the "Disk Space | Virtual Machine Used" metric. The failure to utilize this specific metric is causing the analysis to underestimate the required storage capacity.

Resolution

This issue is known to us and an upcoming patch release is expected to address this issue.

Workaround: Recommended to use manual configuration as the workload in this scenario instead of using "existing VMs" till this issue is permanently fixed.

Additional Information

Refer: What-If Analysis - Infrastructure Planning: Traditional