VM commands (create, start, stop) in Azure - Commands & Configuration

Introduction

Creating and managing virtual machines (VMs) lets you run computers in the cloud. You can start and stop these VMs as needed to save money and control your resources.

When you want to run a Windows or Linux server in the cloud for your app.

When you need to test software on a clean machine without affecting your computer.

When you want to save costs by stopping a VM when it's not in use.

When you want to restart a VM to apply updates or fix issues.

When you want to create multiple VMs for a project or team quickly.

Commands

This command creates a new Ubuntu virtual machine named 'example-vm' in the resource group 'example-rg'. It also sets up SSH keys for secure login.

Terminal

az vm create --resource-group example-rg --name example-vm --image UbuntuLTS --admin-username azureuser --generate-ssh-keys

Expected Output

{

  "fqdns": "",

  "id": "/subscriptions/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx/resourceGroups/example-rg/providers/Microsoft.Compute/virtualMachines/example-vm",

  "location": "eastus",

  "name": "example-vm",

  "powerState": "VM running",

  "resourceGroup": "example-rg",

  "zones": ""

}

→

--resource-group - Specifies the group where the VM will be created

→

--name - Sets the name of the VM

→

--image - Chooses the operating system image for the VM

This command starts the VM named 'example-vm' in the 'example-rg' resource group if it is stopped.

Terminal

az vm start --resource-group example-rg --name example-vm

Expected Output

No output (command runs silently)

→

--resource-group - Specifies the resource group of the VM

→

--name - Specifies the VM to start

This command stops the VM named 'example-vm' in the 'example-rg' resource group to save costs when not in use.

Terminal

az vm stop --resource-group example-rg --name example-vm

Expected Output

No output (command runs silently)

→

--resource-group - Specifies the resource group of the VM

→

--name - Specifies the VM to stop

This command checks the current power state of the VM to confirm if it is running or stopped.

Terminal

az vm show --resource-group example-rg --name example-vm --query instanceView.statuses[1].displayStatus -o tsv

Expected Output

VM stopped

→

--query - Filters output to show only the power state

→

-o - Formats output as plain text

Key Concept

If you remember nothing else from this pattern, remember: creating a VM sets it up, starting powers it on, and stopping powers it off to save costs.

Common Mistakes

Trying to start or stop a VM without specifying the correct resource group.

Azure needs the resource group to find the VM; without it, the command fails.

Always include the --resource-group flag with the correct group name.

Not generating or providing SSH keys when creating a Linux VM.

Without SSH keys, you cannot securely connect to the VM.

Use --generate-ssh-keys or provide your own keys during VM creation.

Assuming stopping a VM deletes it or releases all resources.

Stopping a VM only powers it off; you still pay for storage and reserved resources.

Understand stopping saves compute costs but not storage; delete VM to remove all resources.

Summary

Use 'az vm create' to make a new virtual machine with a chosen OS and login setup.

Use 'az vm start' and 'az vm stop' to control when the VM is running or powered off.

Check VM status with 'az vm show' to confirm its current power state.

Practice

1. What does the az vm create command do in Azure?

easy

A. It starts an existing virtual machine.

B. It stops a running virtual machine.

C. It creates a new virtual machine in Azure.

D. It deletes a virtual machine.

Solution

1. Step 1: Understand the command purpose

   The az vm create command is used to make a new virtual machine in Azure.

2. Step 2: Compare with other commands

   az vm start starts a VM, az vm stop stops it, and az vm delete removes it.

3. Final Answer:

   It creates a new virtual machine in Azure. -> Option C

4. Quick Check:

   az vm create = create VM [OK]

Hint: Create means make new VM, start means turn on, stop means turn off [OK]

Common Mistakes:

• Confusing create with start or stop commands
• Thinking create also starts the VM automatically
• Mixing stop with delete

2. Which of the following is the correct syntax to start a VM named myVM in resource group myGroup?

easy

A. az vm create --name myVM --resource-group myGroup

B. az vm start --name myVM --resource-group myGroup

C. az vm stop --name myVM --resource-group myGroup

D. az vm delete --name myVM --resource-group myGroup

Solution

1. Step 1: Identify the command to start a VM

   The command to start a VM is az vm start.

2. Step 2: Check the syntax for name and resource group

   The correct flags are --name for VM name and --resource-group for the group.

3. Final Answer:

   az vm start --name myVM --resource-group myGroup -> Option B

4. Quick Check:

   Start VM syntax = az vm start [OK]

Hint: Start VM uses 'az vm start' with --name and --resource-group [OK]

Common Mistakes:

• Using create instead of start to power on VM
• Forgetting to specify resource group
• Using stop or delete commands by mistake

3. What will happen if you run this command?

az vm stop --name testVM --resource-group testGroup

medium

A. The VM named testVM will be stopped (powered off).

B. The VM named testVM will be deleted.

C. The VM named testVM will be started.

D. The command will show a syntax error.

Solution

1. Step 1: Understand the command action

   az vm stop stops (powers off) the specified VM.

2. Step 2: Confirm the VM and resource group names

   The VM name is testVM and resource group is testGroup, both valid inputs.

3. Final Answer:

   The VM named testVM will be stopped (powered off). -> Option A

4. Quick Check:

   az vm stop = stop VM [OK]

Hint: Stop command powers off VM, does not delete or start it [OK]

Common Mistakes:

• Confusing stop with delete
• Thinking stop starts the VM
• Assuming syntax error due to names

4. You tried to start a VM with this command:

az vm start -n myVM -g myGroup

The command failed with an error. What is the likely cause?

medium

A. The VM name or resource group might be misspelled or does not exist.

B. You must stop the VM before starting it.

C. The flags -n and -g are incorrect; use full names instead.

D. The az vm start command cannot use short flags.

Solution

1. Step 1: Check command flags

   -n and -g are valid short forms for --name and --resource-group.

2. Step 2: Consider common errors

   Errors usually happen if the VM or resource group name is wrong or missing in Azure.

3. Final Answer:

   The VM name or resource group might be misspelled or does not exist. -> Option A

4. Quick Check:

   Invalid names cause start errors, not flags [OK]

Hint: Check VM and group names carefully if start fails [OK]

Common Mistakes:

• Assuming short flags are invalid
• Thinking VM must be stopped before starting
• Confusing start errors with syntax errors

5. You want to save money by stopping a VM but keep its data intact. Which command should you use and why?

hard

A. Use az vm stop because it powers off the VM but keeps the disk data.

B. Use az vm delete because it stops and removes the VM and data.

C. Use az vm restart because it stops and starts the VM quickly.

D. Use az vm deallocate because it stops the VM and releases compute resources but keeps data.

Solution

1. Step 1: Understand stopping vs deallocating

   az vm stop powers off the VM but does not release compute resources, so charges continue.

2. Step 2: Identify the command to save costs

   az vm deallocate stops the VM and releases compute resources, saving money while keeping disk data.

3. Final Answer:

   Use az vm deallocate because it stops the VM and releases compute resources but keeps data. -> Option D

4. Quick Check:

   Deallocate = stop + release resources + keep data [OK]

Hint: Deallocate stops VM and saves cost without deleting data [OK]

Common Mistakes:

• Using stop only and expecting cost savings
• Deleting VM to save money loses data
• Restarting does not save costs