Azure cost management: budgets, Advisor, savings

Load your subscription ID:

$sub = az account show --query id -o tsv

1See this month’s cost by resource group

Run the Cost Management query API (the same pattern as Lesson 4’s cost-by-lesson):

$q = @{
  type      = 'ActualCost'
  timeframe = 'MonthToDate'
  dataset   = @{
    granularity = 'None'
    aggregation = @{ totalCost = @{ name = 'Cost'; function = 'Sum' } }
    grouping    = @(@{ type = 'Dimension'; name = 'ResourceGroupName' })
  }
}
$q | ConvertTo-Json -Depth 6 | Set-Content -Path C:\azure-lab\cost-by-rg.json
$r = az rest --method post --url "https://management.azure.com/subscriptions/$sub/providers/Microsoft.CostManagement/query?api-version=2023-03-01" --body '@C:\azure-lab\cost-by-rg.json' | ConvertFrom-Json
$r.properties.rows | Sort-Object { $_[0] } -Descending | ForEach-Object { '{0,-14} {1,8:N2} {2}' -f $_[1], $_[0], $_[2] }

You should see something like this:

rg-saat-vms        1.84 USD
rg-saat-core       0.97 USD
rg-saat-data       0.06 USD

Your numbers will differ. If a resource group you deleted still shows cost, that’s normal: it ran earlier this month.

2Add a budget that alerts your action group

A USD 2 monthly budget on rg-saat-vms, alerting at 80% actual and 100% forecast:

$ag = az monitor action-group show --resource-group rg-saat-core --name ag-saat-email --query id -o tsv
$start = (Get-Date -Day 1).ToString('yyyy-MM-01T00:00:00Z')
$b = @{ properties = @{
  category = 'Cost'; amount = 2; timeGrain = 'Monthly'
  timePeriod = @{ startDate = $start }
  notifications = @{
    actual80   = @{ enabled = $true; operator = 'GreaterThan'; threshold = 80;  thresholdType = 'Actual';     contactGroups = @($ag) }
    forecast100 = @{ enabled = $true; operator = 'GreaterThan'; threshold = 100; thresholdType = 'Forecasted'; contactGroups = @($ag) }
  } } }
$b | ConvertTo-Json -Depth 6 | Set-Content -Path C:\azure-lab\budget-vms.json
az rest --method put --url "https://management.azure.com/subscriptions/$sub/resourceGroups/rg-saat-vms/providers/Microsoft.Consumption/budgets/budget-rg-vms?api-version=2023-11-01" --body '@C:\azure-lab\budget-vms.json' --query "{name:name, amount:properties.amount, grain:properties.timeGrain}" -o table

You should see this:

Name           Amount    Grain
-------------  --------  -------
budget-rg-vms  2.0       Monthly

3Ask Advisor for cost recommendations

Run this:

az advisor recommendation list --category Cost --query "[].{impact:impact, problem:shortDescription.problem, resource:impactedValue}" -o table

You may see nothing, or something like this:

Impact    Problem                                                      Resource
--------  -----------------------------------------------------------  ----------
Medium    Right-size or shutdown underutilized virtual machines        web01

Advisor needs a few days of usage data, and your lab VMs are mostly off, so an empty list is common here. In a real subscription, this list is the first place to look each month.

4Price the savings options yourself

Check the reservation and Spot prices for D2s_v5 in Central India:

$f = "serviceName eq 'Virtual Machines' and armRegionName eq 'centralindia' and armSkuName eq 'Standard_D2s_v5'"
$u = 'https://prices.azure.com/api/retail/prices?$filter=' + [uri]::EscapeDataString($f)
(Invoke-RestMethod -Uri $u).Items | Where-Object { $_.productName -notlike '*Windows*' } | Select-Object skuName, type, reservationTerm, retailPrice | Format-Table -AutoSize

You should see something like this:

skuName                     type        reservationTerm retailPrice
-------                     ----        --------------- -----------
Standard_D2s_v5 Spot        Consumption                    0.018665
Standard_D2s_v5 Low Priority Consumption                   0.0202
Standard_D2s_v5             Consumption                    0.101
Standard_D2s_v5             Reservation 1 Year                  546
Standard_D2s_v5             Reservation 3 Years                1048

Reservation prices are the total for the term, not per hour. That’s how the table in the Engineer’s View gets 38.3% and 60.5% savings.

Turn those numbers into a habit. Once a month, spend 20 minutes on Azure cost management: open Cost analysis grouped by resource group, compare with last month, and write down the top three changes and why they happened. Then read Advisor and the orphan query from Break It.

Most teams that do this every month never have a “why is the bill double?” meeting, because they see the change while it is still small.

✅ Checkpoint: You know which resource groups cost the most, budget-rg-vms emails ag-saat-email, and you can price reservations and Spot yourself.