Configure Nerdio Manager Database Resilience

Nerdio Manager allows you to replicate Nerdio Manager's SQL database using failover groups to mitigate the risk of Azure SQL database outages.

See this Microsoft article for an overview of auto-failover groups and best practices.

Create an Azure Database Failover Group

The first step is to create an Azure database failover group in Nerdio Manager. This process includes the following activities:

• Nerdio Manager automates the creation of the second (new) database in the selected region.

• Nerdio Manager then surfaces the new connection string for failover group.

• Nerdio Manager also initiates the replication between the source and replica databases.

To create an Azure database failover group in Nerdio Manager:

1. In Nerdio Manager, navigate to Settings > Nerdio environment.

2. In the Nerdio Manger database replication tile, select Configuration.

3. Select Create failover group.

4. From the drop-down list, select the Location of the secondary database and then select OK.

   The failover group creation process starts. You can follow its progress in the Settings Tasks window.

   The new Failover Group is now displayed in the configuration details. This includes the new connection string.

   

Edit the Database Connection String in Azure

The next step is to edit the database connection string in Azure.

To edit the database connection string in Azure:

1. In the Azure portal, sign in as an administrative user with permissions to access the key vault and create/modify values.

2. Navigate to Key vaults.

3. Select the Key Vault associated with the Nerdio Manager instance.

   Note: This resource is prefixed by default with nmw-app-kv.

4. On the left, in the Objects blade, select Secrets.

5. Select the ConnectionStrings--DefaultConnection secret.

6. Copy the current value of the Secret value.

   Tip: It is strongly recommended that you store the current value securely for future reference in case you wish to undo the failover configuration and revert to your previous configuration.

   

7. In Notepad, paste the current value of the Secret value.

8. In Nerdio Manager, navigate to Settings > Nerdio environment.

9. In the Nerdio Manger database replication tile, select Configuration.

10. At the bottom, in the Endpoint, copy the endpoint to the clipboard.

    

11. In Notepad, replace Server=tcp:nmw-app-sql-zt243xkddsf6ho.database.windows.net,1433 with the new endpoint you copied from Nerdio Manager.

    For example, the edited Secret value should look like: Server=tcp:9eb62920-f85f-4b25-9059-0d1b3789c5c6.database.windows.net,1433.

12. Copy the edited Secret value to the clipboard.

13. In the Azure portal, in the Connection Strings key vault, select + New Version.

    

14. In Secret value, paste the edited Secret value from the clipboard.

    

15. Select Create.

    The new version is created.

16. Restart the app service.

Failover

By default, the Nerdio Manager failover configuration is set to Automatic. Therefore, if the Azure platform detects an outage for the primary database, it automatically performs a failover operation to the secondary database. In addition, it performs a failback operation when the outage is fixed.

The default configuration can be changed to Manual from the Edit configuration option in the Azure SQL Failover configuration screen shown below. If the failover group is configured for Manual failover and failback, you must manually perform the failover and failback.

To manually failover to the secondary database:

1. In the Azure portal, navigate to the failover group.

   

2. Select the failover group and then select either Failover or Forced Failover.

   Note:

   • Failover performs full data synchronization between the primary and secondary databases before the secondary switches to the primary role. This guarantees no data loss.

   • Forced Failover immediately switches the secondary to the primary role without waiting for recent changes to propagate from the primary. This operation may result in data loss.