2022-Azure-ScaleUpVMWhenCPUPerformanceOver80

A. Overview

Purpose of this presentation:

If CPU Performance >10% within 1 min, VM will automatically scale up to higher level of configuration
Based on this flow, User can set up other automation cases for VM on their own such as Scale down, Restart, Stop or Start

Scale up Rule: VM sizes scaling pair Ex: | | Basic_A0 | Basic_A4 | | Standard_A0 | Standard_A4 | | Standard_A5 | Standard_A7 | | Standard_A8 | Standard_A9 | | Standard_A10 | Standard_A11 | | Standard_D1 | Standard_D4 | | Standard_D11 | Standard_D14 | | Standard_DS1 | Standard_DS4 | | Standard_DS11 | Standard_DS14 | | Standard_D1v2 | Standard_D5v2 | | Standard_D11v2 | Standard_D14v2 | | Standard_G1 | Standard_G5 | | Standard_GS1 | Standard_GS5 |
Issue I faced on this task:

Select the Runbook version that is not compatible with the Module in Automation Account
Add Role for User-assigned managed identity in the wrong way, so running fails

I refer to this link. However, Azure has changed over time and the approach has been improved

https://github.com/uglide/azure-content/blob/master/articles/virtual-machines/virtual-machines-windows-vertical-scaling-automation.md

B. Summary of flow

I> Create User-assigned managed identity

Ref: https://learn.microsoft.com/en-us/azure/active-directory/managed-identities-azure-resources/how-manage-user-assigned-managed-identities?pivots=identity-mi-methods-azp

1. There are 2 ways approaching Automation Account

system-assigned managed identity
User assign managed identity

I follow the second one

2 Assign permissions to managed identities

Ref: https://learn.microsoft.com/en-us/azure/automation/automation-create-alert-triggered-runbook

Follow steps on the above link, summary as follows:

2.1 Provide variables

$resourceGroup = "resourceGroup"
$automationAccount = "AutomationAccount"
$userAssignedManagedIdentity = "userAssignedManagedIdentity"

$resourceGroup = "testscaleuprg"
$automationAccount = "lytntautoaccount"
$userAssignedManagedIdentity = "UAI1"

2.2 Use PowerShell cmdlet New-AzRoleAssignment to assign a role to the system-assigned managed identity.

$SAMI = (Get-AzAutomationAccount -ResourceGroupName $resourceGroup -Name $automationAccount).Identity.PrincipalId
New-AzRoleAssignment `
    -ObjectId $SAMI `
    -ResourceGroupName $resourceGroup `
    -RoleDefinitionName "Contributor"

##Role "Virtual Machine Contributor" may be okay

##Wait result this step

2.3 Assign a role to a user-assigned managed identity.

$UAMI = (Get-AzUserAssignedIdentity -ResourceGroupName $resourceGroup -Name $userAssignedManagedIdentity)
New-AzRoleAssignment `
    -ObjectId $UAMI.PrincipalId `
    -ResourceGroupName $resourceGroup `
    -RoleDefinitionName "Contributor"

##Wait result this step

2.4 final

$UAMI.ClientId

##save id: 6132e277-8327-41e5-9671-105033dad25d

##img2: the result as line3 in the image

II> Tạo Virtual VM- Ubuntu

The Cheapest VM config: Standard B1s (1 vcpu, 1 GiB memory)

upgraded vm=> Standard B2s (2 vcpus, 4 GiB memory)

Networking: open port 22
Tick Delete Public ip when VM is deleted
Enable System assigned managed identity
Login with Azure AD
Download key and create vm

III> Create Automation Account and Runbook

Tab Advanced, tick System assigned và User assigned
Add user assigned identities, ex UAI1
Networking: choose Public access

III.2 Create Runbook for scale up VM

Name:
Runbook Type: PowerShell
Runtime version: 5.1 Note:This version will compatible with Module (in Automation Account-vd:lytntautoaccount=> Module)
Code của Runbook có thể Import từ Gallery

EX: ScaleUp-Azure-VM-On-Alert

author: azureautomation

Save=> Publish

IV. Create Alert

Ref: https://learn.microsoft.com/en-us/azure/automation/automation-create-alert-triggered-runbook

1 Scope

Filter by resource type: Virtual machines
Click choose vm you want to scale up

##img5: Interface of Alert rule scope

2. Condition

choose CPU Percentage

#If CPU percentage >10% within 1 min => alert fired

Threshold value: 10
Lookback period: 1

3. Action

Create action group

Send email when alert fired
Action type: Automation Runbook

Runbook Source: User
Subscription -> select Automation account created above -> select runbook of scaleup published
Enable Alert Schema

4. Name for alert and create

5. Check alert rule attached on VM

V> Access VM and test

#git bash

cd ~
cd Desktop/

#Connect to VM

ssh -i misasinglevm_key.pem azureuser@20.234.37.207

#Download stress module to push CPU upto 100%

sudo apt-get update
sudo apt-get -y install stress
sudo stress --cpu 1 --timeout 2000

#To observe, open new git window, type command:

htop

#Result: Check mail and Refresh VM

orgiginal vm: Standard B1s (1 vcpu, 1 GiB memory)
upgraded vm: Standard B2s (2 vcpus, 4 GiB memory)

LyTNT / 2022-Azure-ScaleUpVMWhenCPUPerformanceOver80-