Critical alarm "Datastore usage on disk" reported on vCenter UI.

Products

• VMware vSphere ESXi

Issue/Introduction

• "Datastore usage on disk" critical alarms are reported on  "vCenter UI > Triggered alarms"

 

 

Environment

VMware vSphere ESXi 8.x

Cause

• This alarm is triggered when the datastore utilization is above the threshold provided in the vCenter alarm definition.
• In vCenter UI, vCenter > Monitor > Alarm Definitions > Datastore usage on disk  will show the threshold in that environment.

Resolution

To fix the datastore space issue:

• Free up the space on datastore by deleting unnecessary ISO files, templates, old snapshots, etc.

• Migrate the VM to another datastore with sufficient space available

         https://techdocs.broadcom.com/us/en/vmware-cis/vsphere/vsphere/9-1/vcenter-and-host-management/migrating-virtual-machines/migration-with-vmotion/migration-with-storage-vmotion/migrate-a-virtual-machine-with-storage-vmotion.html 

• If above steps are not possible, expand the datastore capacity at the storage level and increase the space from the ESXi level accordingly 

https://techdocs.broadcom.com/us/en/vmware-cis/vsphere/vsphere/8-0/vsphere-storage/working-with-datastores-in-vsphere-storage-environment/managing-vsphere-vmfs-datastores/increase-capacity-of-vsphere-vmfs-datastore.html 

Additional Information

View Alarm Definitions