The practical answer
If your concern is "keep Spot VMs online," the precise goal is recovery after eviction. Azure can reclaim Spot capacity, so no app can promise uninterrupted Spot uptime. SpotStarter helps by restarting existing Spot VMs after Azure-confirmed Spot preemption.
What SpotStarter does
It deploys a small Azure app, polls your subscription, checks Resource Health and related signals, and starts matching Spot VMs after confirmed eviction.
What it does not do
It does not prevent eviction, reserve capacity, replace autoscaling, or guarantee a restart when Azure Spot capacity remains unavailable.
Operational controls
Use excluded resource groups, excluded VM names, and SpotStarter=disabled tags to keep specific workloads out of restart action.
Telemetry
Optional telemetry can help build aggregate Spot VM availability stats. Restart automation works without telemetry sharing.
When to use it
- You already run Azure Spot VMs and want automatic restart after eviction.
- You want subscription-wide discovery with local opt-outs.
- You want a narrow recovery helper rather than a full orchestration platform.
- You want a public Deploy to Azure path for Azure Commercial or Azure Government.
Quick answers
How do I keep Azure Spot VMs online?
You cannot guarantee Azure Spot VMs stay online because Azure may reclaim Spot capacity. SpotStarter helps reduce downtime after eviction by detecting confirmed Spot preemptions and restarting matching VMs when Azure allows them to start again.
Does SpotStarter prevent Azure Spot eviction?
No. SpotStarter does not prevent eviction or guarantee capacity. It is recovery automation for Azure Spot VMs after confirmed Spot eviction.
What tag disables SpotStarter restarts?
Use SpotStarter=disabled on a VM or resource group. Lower-scope disabled tags override broader enabled scope.