az vm create: Provision a Virtual Machine

az vm create provisions a virtual machine with the image, size, and networking you specify.

Ephemeral VMs back load tests and self-hosted runners. vm create spins one up, and the JSON it returns carries the IP you need for the next step.

What it does

az vm create provisions a VM in a resource group, creating a NIC, OS disk, and (by default) a public IP. It returns a JSON object with publicIpAddress and other details once the machine is running.

Common usage

Terminal

az vm create \
  --resource-group rg-app --name vm-runner \
  --image Ubuntu2204 --size Standard_B2s \
  --admin-username azureuser --generate-ssh-keys \
  --query publicIpAddress -o tsv

Subcommands and flags

Flag	What it does
--resource-group, -g	Target resource group
--name, -n	VM name
--image	OS image alias or URN, e.g. Ubuntu2204
--size	VM SKU, e.g. Standard_B2s
--admin-username	Initial admin account
--generate-ssh-keys	Create SSH keys if absent
--public-ip-address ""	Omit a public IP (private-only VM)

In CI

Capture the address with --query publicIpAddress -o tsv to feed an SSH or smoke-test step. For private runners pass --public-ip-address "" and reach the VM over the VNet. Tag throwaway VMs so a cleanup job can find them.

Common errors in CI

"QuotaExceeded ... exceeding approved Total Regional Cores quota" means the region is at its core limit; choose a smaller size or another region. "InvalidParameter: The value of parameter adminUsername is not allowed" rejects names like admin or root. "AuthorizationFailed" on the write action means the identity lacks Contributor.