vCenter Snapshot Size Alarm Fails to Trigger with Multiple Threshold Conditions Configured

Products

• VMware vCenter Server 8.0
• VMware vCenter Server

Issue/Introduction

In VMware vCenter Server, users may experience a situation where a custom Snapshot Size Alarm fails to trigger or send notifications. This occurs specifically when both Warning (Yellow) and Critical (Red) threshold conditions are defined within a single alarm rule. Despite the snapshot size exceeding the defined limits, the alarm status remains unchanged and no actions are executed.

Environment

vCenter Server 7.x

vCenter Server 8.x

Cause

A logic conflict occurs within the alarm evaluation engine where the Red (Critical) state and Yellow (Warning) state effectively overwrite each other during the same polling cycle. This race condition prevents the alarm from successfully transitioning to either triggered state, resulting in both conditions being ignored.

Resolution

This issue is scheduled to be addressed in a future release of vCenter Server.

 

To resolve this behavior in current versions, implement the following workaround:

1. Log in to the vSphere Client.

2. Navigate to the Alarms configuration for the affected object (e.g., Datacenter or Cluster).

3. Delete or disable the single alarm containing both threshold conditions.

4. Create two separate alarm rules:

   • Alarm 1 (Warning): Configure only the Warning (Yellow) threshold condition and associated actions.

   • Alarm 2 (Critical): Configure only the Critical (Red) threshold condition and associated actions.

5. Save both alarms.

By isolating the thresholds into independent alarms, the evaluation engine can trigger each status correctly without state overwriting.