Azure Scale Application - Increase Or Decrease the number of role Instance

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Undoubtedly one of the best feature of Windows Azure is to allow you scale your hosted service based on demand by increasing and decreasing number of role instances part of your hosted service. This not only helps business with increases customer satisfaction but also save cost.

 

Behind the Scene

This is achieved by defining the Value of role instance count in the Instances element within the service configuration file. Now as and when needed you can update service configuration file.

 

 <Role name="XYZ">
    <Instances count="1" />
    <ConfigurationSettings> 

 

How to Increase Or Decrease the number of Role Instance

Scaling of application can be done in multiple ways

  •  Using Windows Azure Portal , I found this article really useful to perform this task

    • by modifying existing service configuration file

    • by uploading new updated service configuration file

  • Using Rest API - The Windows Azure Service Management REST API also exposes operations allowing the service configuration to be replaced with a new version containing different instance counts for the roles.

  • Using Set-RoleInstanceCount Windows Azure Platform PowerShell cmdlets, which allow various Service Management REST API operations to be invoked directly from PowerShell.

 

For one of my recent project i created following is powershell code

 

Increase the number of role Instance

cls
Add-PSsnapin AzureManagementToolsSnapin
Add-PsSnapin WAPPSCmdlets
#Subscription-Id of my Subscription
$subscriptionId = '8a27c306-9434-4d59-971a-c3dc82dcwerew'
#Thumbprint of certificated used to manage Subscriptin. This certificated should be already added to subscription
$Certificate = Get-Item cert:\LocalMachine\My\22598061DFB6543663E2D1A4C70045F528234
$hostedServiceName ='hostedservicename'
$slot="Production"
$rolename="RoleName"
$rolecount=(Get-RoleInstanceCount -SubscriptionId $subscriptionId -Certificate $Certificate -DeploymentSlot $slot -RoleName $rolename -ServiceName $hostedServiceName).instancecount
$rolecount=$rolecount + 1  
Set-RoleInstanceCount -SubscriptionId $subscriptionId -Certificate $Certificate -DeploymentSlot $slot -RoleName $rolename -ServiceName $hostedServiceName -Count $rolecount | Get-OperationStatus -WaitToComplete  
Remove-PSsnapin AzureManagementToolsSnapin
Remove-PSsnapin WAPPSCmdlets

 

 Decrease the number of Role Instance

cls
Add-PSsnapin AzureManagementToolsSnapin
Add-PsSnapin WAPPSCmdlets
#Subscription-Id of my Subscription
$subscriptionId = '8a27c306-9434-4d59-971a-c3dc82dcwerew'
#Thumbprint of certificated used to manage Subscriptin. This certificated should be already added to subscription
$Certificate = Get-Item cert:\LocalMachine\My\22598061DFB6543663E2D1A4C70045F528234
$hostedServiceName ='hostedservicename'
$slot="Production"
$rolename="RoleName"
$rolecount=(Get-RoleInstanceCount -SubscriptionId $subscriptionId -Certificate $Certificate -DeploymentSlot $slot -RoleName $rolename -ServiceName $hostedServiceName).instancecount
$rolecount
if ($rolecount -gt 1)
 {
  $rolecount=$rolecount - 1
  $rolecount
  Set-RoleInstanceCount -SubscriptionId $subscriptionId -Certificate $Certificate -DeploymentSlot $slot -RoleName $rolename -ServiceName $hostedServiceName -Count $rolecount | Get-OperationStatus -WaitToComplete
 }
Remove-PSsnapin AzureManagementToolsSnapin
Remove-PSsnapin WAPPSCmdlets

 

I am sure you will find this article helpful. Please rate this article and share your comments. For more details please feel free to contact me at arunrakwal@yahoo.com and I will be happy working with you.