# Recheck Spot recovery ownership when enabling scale-set autoscale

> Will Spot Try & restore keep maintaining the target count after autoscale is enabled?

- Canonical URL: https://update.dsesecurity.com/updates/dse-20260909-532-recheck-spot-recovery-ownership-when-enabling-scale-set-autoscale/
- Publisher: Detection Systems & Engineering (DSE Security)
- Author: DSE Security Editorial Team
- Published: 2026-09-10T00:23:04+00:00
- Modified: 2026-09-10T02:11:18+00:00
- Last reviewed by DSE: 2026-09-09
- Resource type: Guide
- DSE priority: Information
- Topics: Business Continuity, IT
- Reading time: 2 minutes

## What you need to know

Will Spot Try & restore keep maintaining the target count after autoscale is enabled?

## Potentially affected

Azure Spot VM scale sets whose owners are changing between Try & restore and autoscale-driven capacity management.

## DSE recommendation

Assign one explicit recovery expectation to the scale set's selected capacity-control configuration.

## Article

## Source facts

Spot Try & restore attempts to recover capacity-evicted instances in a scale set to maintain its target instance count. The feature is disabled when the scale set uses Autoscale; autoscale rules then drive the number of VMs. Microsoft also cautions that autoscaling can attempt to replace evicted Spot capacity but does not guarantee successful allocation. [Microsoft Learn](https://learn.microsoft.com/en-us/azure/virtual-machine-scale-sets/use-spot).

## Applicability

Use this check when adding autoscale to an existing Spot workload or explaining why the previously expected restore mechanism is not acting. Confirm the current controller and eviction policy before attributing a reduced instance count to a failed repair.

## DSE recommendation

Assign one explicit recovery expectation to the scale set’s selected capacity-control configuration. Have the workload owner state what should happen after capacity loss and compare that expectation with the actual autoscale rules. Review whether the workload can tolerate a period below its desired population. Keep allocation uncertainty in the operating plan rather than promising that either mechanism restores capacity immediately.

## Verification

Use an authorized eviction simulation on a disposable instance and observe the selected mechanism’s response. Track the target count, actual instances and any unsuccessful replacement attempt. Verify application work completion separately from the population count. After changing autoscale configuration, revisit the recovery record so responders do not rely on a Try & restore setting that is inactive under the new configuration.

## Official references

[Microsoft Learn: Azure Spot Virtual Machines for Virtual Machine Scale Sets](https://learn.microsoft.com/en-us/azure/virtual-machine-scale-sets/use-spot). Source reviewed September 9, 2026.

## Primary reference

- Name: Create a scale set that uses Azure Spot Virtual Machines - Azure Virtual Machine Scale Sets | Microsoft Learn
- Authority: Microsoft Learn
- URL: https://learn.microsoft.com/en-us/azure/virtual-machine-scale-sets/use-spot
- Source publication date: Not stated by the source

## Citation and use

Preferred citation: “Recheck Spot recovery ownership when enabling scale-set autoscale,” DSE Security, https://update.dsesecurity.com/updates/dse-20260909-532-recheck-spot-recovery-ownership-when-enabling-scale-set-autoscale/
Publishing principles: https://update.dsesecurity.com/updates/dse-updates-editorial-methodology/
Usage and citation policy: https://update.dsesecurity.com/usage/
Copyright © 2026 Detection Systems & Engineering. All rights reserved.