One of the great things that came with the plethora of new features and capabilities around Azure networking at Build 2015 and didn’t get a lot of attention is the fact that now you have much more flexibility in working with reserved IP addresses in your deployments. By default, VIP addresses of Azure cloud services are dynamic by nature, i.e. they may change when VMs get de-provisioned or the Azure fabric needs to move your VMs to another host, e.g. due to hardware failure.
What you can do now with the latest release of the Azure PowerShell Cmdlets is to convert existing dynamic VIP to reserved IP addresses. Doing so will take the current cloud service VIP from the data center’s general IP address pool and assign it specifically as a reserved IP to your Azure subscription. The IP will remain associated with the cloud service deployment, but can also be used for other deployments in your subscription, as we will see in this post.