Add instance to Windows Azure Cloud Service

Question

I have an Azure Cloud Service out in production. I recently received the following message from Microsoft about upcoming service for their Cloud Services platform:

All Cloud Services running web and/or worker roles referenced below will experience downtime during this maintenance. Cloud Services with two or more role instances in different upgrade domains will have external connectivity at least 99.95 percent of the time. Please note that the SLA guaranteeing service availability only applies to services that are deployed with more than one instance per role. Azure updates one upgrade domain at a time. For more information about distribution of roles across upgrade domains and the update process, please visit the Update an Azure Service webpage.

The way I take the email, each instance is essentially a VM on a different host, and they'll be rebooting hosts throughout the maintentance period, so if I don't want to be out of service during this time, I need to ensure I have more than one instance. Is this accurate? If so, how do I "add" an instance?

Answer 1

That is correct.

You can increase your instance count by updating the configuration for the role. In Visual Studio, you can do this in the Properties window for the role and increase the Instance count setting. Then, redeploy the service.

A faster way is to download the configuration file (.cscfg) for the role from the Azure portal, update the instance count setting, and then upload the changed configuration file. The setting is in the Instances element shown here.

You can download the configuration file for the role from the Azure portal (portal.azure.com) by going to the Cloud Service blade and clicking on Settings in the toolbar. In the Settings blade click Configuration. In the Configuration blade are where you will find Download and Upload buttons in the toolbar.

Answer 2

The way I take the email, each instance is essentially a VM on a different host, and they'll be rebooting hosts throughout the maintentance period, so if I don't want to be out of service during this time, I need to ensure I have more than one instance. Is this accurate?

Your understanding is correct.

If so, how do I "add" an instance?

There are many ways to do it.

One would be to edit your role's configuration file (*.cscfg) and changing the Instances element's count property from 1 to 2 and then uploading this file through Azure Portal (Cloud Service --> Configure Tab --> Upload button)

Other one would be to change the instance count through "Scale" tab for Cloud Service in question. On this tab, you will see "Instance Count" setting. Just update it from 1 to 2.

Other options include PowerShell, writing code but I think the ones I mentioned above should be the easiest way to accomplish the task.