Azure / Guide 10

Cost hygiene

Budgets, the monthly clean-up checklist, reservations and savings plans.

Most Azure waste comes from a handful of habits: resources nobody deleted, VMs running when nobody uses them, sizes chosen once and never revisited, and paying full price for steady workloads. This guide covers the checks and fixes that pay back quickly. The FinOps topic will cover the wider practice: showback, forecasting and working with finance.

See where the money goes

Cost Management + Billing in the portal is the starting point:

Cost analysis: group by service, resource group, or tag (for example CostCenter) to see who spends what.
Tag inheritance (Cost Management settings): applies resource group and subscription tags to cost records, so reports by tag are complete.
Exports: a daily export to a storage account gives you the detailed data for Power BI or Excel.

Set budgets and alerts

A budget doesn't stop spending, but it tells people before the invoice does. Create one per subscription (or per resource group for big projects) with alerts at 80%, 100% and a forecast of 100%:

New-AzConsumptionBudget -Name 'budget-notes-test-monthly' -Amount 2000 -Category Cost `
    -TimeGrain Monthly -StartDate (Get-Date -Day 1).Date `
    -ContactEmail 'jane@ravindran.in' -NotificationKey 'Actual80' -NotificationThreshold 80 -NotificationEnabled

Forecast alerts are easiest to add in the portal (Cost Management > Budgets).

The monthly clean-up checklist

Orphaned resources. Unattached disks, unused public IPs, detached NICs, empty resource groups and old snapshots. Find-AzOrphanedResources.ps1 lists them across every subscription. Unattached premium disks and Standard SKU public IPs are billed whether they're used or not.
Stopped but not deallocated VMs. They're still billed for compute. Check the PowerState column in Get-AzVMInventory.ps1.
Non-production running 24/7. Schedule it with Invoke-AzVMPowerSchedule.ps1.
Azure Advisor cost recommendations. Right-size or shut down underused VMs, and delete idle resources. Review them monthly; they refresh as usage changes.
Untagged resources. Costs without an owner never get reviewed. Run Get-AzUntaggedResources.ps1.

Pay less for what you keep

Option	Best for	Commitment
Reservations	A specific VM family (or database, storage) running steadily in one region	1 or 3 years, for that resource type
Azure savings plan for compute	Steady compute spend that moves between VM sizes, regions or services	1 or 3 years, an hourly spend amount
Azure Hybrid Benefit	Windows Server and SQL Server licenses you already own with Software Assurance	Your existing licenses
Dev/Test pricing	Non-production subscriptions for Visual Studio subscribers	Dev/Test subscription offer
Spot VMs	Interruptible batch work	None; can be evicted at short notice

Microsoft quotes discounts of up to about 72% for reservations and about 65% for savings plans compared with pay-as-you-go, depending on the service and term. The usual approach: right-size first, then cover the steady baseline with reservations or a savings plan, and leave the variable part on pay-as-you-go. Review utilisation monthly in Reservations and Savings plans.

Storage and logs

Blob lifecycle management: move data to cool, cold and archive tiers automatically after a number of days, and delete it when it's no longer needed.
Snapshots are easy to create and forget; set a retention rule.
Log Analytics: check what's ingesting the most (see the monitoring guide). Verbose diagnostic logs can cost more than the resources they describe.

Make it routine

Put a 30-minute cost review in the calendar each month with the people who own the biggest subscriptions. Look at the trend, the top five resources, Advisor recommendations and the orphaned resources report. Small, regular clean-ups beat an annual cost-cutting project.