Read Scale-Out

Overview

This section provides instructions on how to configure the optional Read Scale-Out feature, which allows load balancing of SQL Database read-only workloads using a read-only replica rather than a read-write replica. For more information on this feature, see the Use read-only replicas to load balance read-only query workloads (preview) Microsoft article.

Prerequisites

• Make sure to have either a Premium or a Business Critical service tier.

• You must have permissions to make changes to the database in the Azure portal.

Read Scale-Out configuration

Step 1: Enable the Read Scale-Out feature in PowerShell

1. Install or update the Azure PowerShell module in PowerShell by running the following commands:

   Install-Module -Name AzureRM -AllowClobber
   Import-Module -Name AzureRM

   For more information, see Install Azure PowerShell on Windows with PowerShellGet.

2. Log in to your Microsoft Azure account in PowerShell by running the following command:

   Login-AzureRmAccount

   If you encounter any security issues with the Microsoft Azure sign-in process, then you must manually add https://login.microsoftonline.com/ and all related websites' URIs to the Trusted sites zone in Internet Explorer's Internet Options.

3. Enable the Read Scale-Out feature in PowerShell by running the following command:

   Set-AzureRmSqlDatabase -ResourceGroupName <resource group> -ServerName <server name> -DatabaseName <database name> -ReadScale Enabled

   • Replace <resource group> with the resource group name.

   • Replace <server name> with the server name (e.g. workflowgen.database.windows.net).

   • Replace <database name> with the database name (e.g. WFGEN).

You can also enable Read Scale-Out feature using the Azure SQL Database Rest API.

Step 2: Configure WorkflowGen

1. Go to the Database section on the Configuration Panel General tab.

2. In the Master database connection string field, add the ApplicationIntent=ReadWrite parameter to the existing connection string and click Test to test the database availability. Here's an example of a connection string:

   Data Source=workflowgen.database.windows.net;Initial Catalog=WFGEN;User ID=wfgen_user;Password=Admin123!;encrypt=true;trustServerCertificate=false;ApplicationIntent=ReadWrite;

3. In the Read-only database connection string field, add (or edit) the connection string with the new ApplicationIntent=ReadOnly parameter, and click Test to test the database availability. Here's an example of a connection string:

   Data Source=workflowgen.database.windows.net;Initial Catalog=WFGEN;User ID=wfgen_user;Password=Admin123!;encrypt=true;trustServerCertificate=false;ApplicationIntent=ReadOnly;

4. Check the Multi-database option.

5. Check the User Portal components and modules that will use the Read-only database. For more information about this, see Database in the WorkflowGen Administration Guide.