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Remediation

Considerations​

  1. Virtual machines (VMs) with local temporary disks cannot be resized to VM SKUs that do not support temporary disks, and vice versa.
  2. Resizing from a SCSI-based VM SKU to a remote NVMe-enabled VM SKU is not supported.

Right-Sizing UNderutilized Virtual Machine​

Resizing a VM should be treated as a disruptive operation, particularly for stateful workloads. Ensure proper planning and downtime windows if required.

For VMs leveraging Premium Storage, it is critical to select an s-series SKU to retain support. For instance, use Standard_E4s_v3 instead of Standard_E4_v3 to maintain Premium disk compatibility.

Azure CLI​

resourceGroup={{resource-group-name}}
vmName={{vm-name}}
newSize={{desired-vm-size}}

# Deallocate the VM
az vm deallocate --resource-group $resourceGroup --name $vmName

# Resize the VM
az vm resize --resource-group $resourceGroup --name $vmName --size $newSize

# Start the VM
az vm start --resource-group $resourceGroup --name $vmName

PowerShell​

$resourceGroup = "{{resource-group-name}}"
$vmName = "{{vm-name}}"
$newSize = "{{desired-vm-size}}"

# Deallocate the VM
Stop-AzVM -ResourceGroupName $resourceGroup -Name $vmName -Force -NoWait

# Resize the VM
Update-AzVM -VM (Get-AzVM -ResourceGroupName $resourceGroup -Name $vmName | Set-AzVMSize -Size $newSize) -ResourceGroupName $resourceGroup

# Start the VM
Start-AzVM -ResourceGroupName $resourceGroup -Name $vmName

Implementing Auto-Scaling​

For workloads with variable resource demands, whether predictable or bursty, consider transitioning to a Virtual Machine Scale Set (VMSS) with auto-scaling rules. This allows for dynamic adjustment of VM instance count based on real-time performance metrics.

  • If the existing workload is not deployed on a VMSS, migration to a VMSS-based deployment model will be required.

  • Configure scaling rules to increase instance count (scale out) when metrics such as average CPU utilization exceed thresholds (e.g., 80%), and decrease count (scale in) when utilization drops below a defined baseline.

Consolidating Workloads​

In scenarios where multiple underutilized VMs host related or complementary workloads, evaluate the feasibility of consolidating these workloads onto a single, appropriately sized VM.

  • Carefully orchestrate the migration of services and data.
  • Once consolidation is verified, decommission the original VMs by stopping and deleting them.

Decommissioning Underutilized Virtual Machines​

If a VM is no longer required or its workload has been migrated, consider the following actions to eliminate unnecessary resource costs:

Stopping (Deallocating) the VM​

This action stops the VM and releases compute resources. Billing for compute is paused, but charges for persistent resources (e.g., OS and data disks, reserved IPs) continue.

Azure CLI​

az vm deallocate --resource-group {{resource-group-name}} --name {{vm-name}}

PowerShell​

Stop-AzVM -ResourceGroupName "{{resource-group-name}}" -Name "{{vm-name}}"

Terminating (Deleting) the VM​

This permanently deletes the VM. Use caution—ensure data has been fully migrated or backed up prior to deletion.

To preserve the disk for future reuse, configure the OS disk's delete option to "detach":

az resource update 
    --resource-group {{resource-group-name}} \
    --name {{vm-name}} \
    --resource-type virtualMachines \
    --namespace Microsoft.Compute \
    --set properties.storageProfile.osDisk.deleteOption=detach

Before terminating, ensure all necessary data has been backed up or migrated.

Azure CLI​

az vm delete --resource-group {{resource-group-name}} --name {{vm-name}} --yes

PowerShell​

Remove-AzVm -ResourceGroupName "{{resource-group-name}}" -Name "{{vm-name}}" -Force

If there is no intention to reuse any VM resources, it is recommended to explicitly delete all associated components after the VM is removed to avoid unnecessary costs. These resources typically include:

  • OS and data disks
  • Network interfaces (NICs)
  • Public IP addresses
  • Network security groups (NSGs)
  • Load balancer rules (if applicable)
  • Virtual machine boot diagnostics storage (if enabled)