VM Downgrade
VM Downgrade lets a customer move an existing VM to a lower compute plan (CPU / memory) through Change Plan.
Applicable providers: CloudStack, OpenStack
VM Downgrade is available only when all of the following are true:
| Requirement | Required value |
|---|---|
| Billing cycle | Hourly only — not monthly or other cycles |
| Enable Override Disk Offering (Cloud Provider Setup) | Yes |
| Enable Change Plan (Cloud Provider Setup) | Yes |
Global setting downgrade_vm | true |
If override disk is not enabled, or the VM is not hourly, or downgrade_vm is false, downgrade is not applicable.
Prerequisites (admin)
Update these settings before customers can downgrade.
1. Cloud Provider Setup — Enable Change Plan
Path: Cloud Provider setup / Provider Config for the CloudStack or OpenStack provider.
Enable Change Plan
Required for downgrade. Set to Yes.
| Value | Effect |
|---|---|
| Yes | Change Plan (including downgrade to a lower package) is available for this provider |
| No | Change Plan is not offered for this provider |
Related: OpenStack — Enable Change Plan · CloudStack Provider Config on Connecting
2. Cloud Provider Setup — Enable Override Disk Offering
Enable Override Disk Offering
Required for downgrade. Set to Yes.
Downgrade is supported only when storage is not bundled inside the compute offering — compute-only packages with override disk. With override disk No (storage bundled in compute), VM downgrade is not supported.
Related: CloudStack — override disk · OpenStack — override disk
Enable Override Disk Offering is an infrastructure decision for the cloud provider setup. Do not turn it on or off later for a live environment — changing it in between can affect existing customers and resources.
- Decide Yes (compute-only + override disk) or No (storage bundled) during initial Cloud Provider Setup, before production packages and VMs.
- If this setting is currently No / false and you need VM Downgrade, contact the StackConsole team before making any change. Do not flip the flag yourself on a running deployment.
3. Global settings — downgrade_vm
Path: CMP global settings
downgrade_vm
Required. Set to true.
| Value | Effect |
|---|---|
true | Downgrade via Change Plan is allowed (subject to hourly + override disk + Enable Change Plan) |
false | Downgrade VM is not applicable — even if Change Plan and override disk are enabled |
downgrade_vm must be trueIf downgrade_vm is false, customers cannot downgrade. Enable Change Plan alone is not enough.
Applicable billing cycles
| Billing cycle | Downgrade |
|---|---|
| Hourly | Supported |
| Monthly / other cycles | Not supported |
Only VMs created (or billing) on an hourly cycle can use VM Downgrade.
How it works
- Customer opens the VM → Overview → Settings → Change Plan
- Selects a lower plan than the current offering and confirms the update
- CMP soft-deletes the current offering and creates a new offering with the new plan and billing
- From that point on, the VM is charged at the new hourly rate for remaining hours in the billing period
Detailed billing example
| Item | Value |
|---|---|
| VM billing cycle | Hourly |
| VM configuration | 8 Core, 12 GB Memory |
| Per-hour cost | $2 |
| Downgrade after | 120th hour |
| Downgraded configuration | 4 Core, 8 GB Memory |
| Per-hour cost after downgrade | $1 |
From the 120th hour, this VM is charged at $1/hour.
If the VM runs until the end of the month and total hours are 300:
| Period | Hours | Rate | Charge |
|---|---|---|---|
| Before downgrade | 120 | $2/hour | $240 |
| After downgrade | 180 | $1/hour | $180 |
| Total for the month | 300 | $420 |
Calculation: 120 × $2 + 180 × $1 = $420
CMP’s minimum charge unit for hourly VMs is hours. If a VM is downgraded partway through an hour, that full hour is still charged.
The same hour can be charged under both the old and the new rates — time before the downgrade at the previous plan price, and time after at the new plan price.
Customer path
Path: VM details → Overview → Settings → Change Plan → select a lower plan → update
Checklist
- Provider is CloudStack or OpenStack
- Enable Change Plan = Yes on the cloud provider setup
- Enable Override Disk Offering = Yes on the cloud provider setup
- Global
downgrade_vm=true - Target VM uses hourly billing
- Customer selects a lower plan via Change Plan
Related
- Virtual Machine
- CloudStack — Virtual Machine packages
- OpenStack — Virtual Machine packages
- Billing cycles — Hourly
- Stoppable services — also works best with override disk