Azure Reserved Instance - Any advantage to shutting down VMs?

Occasional Contributor

With a Pay-As-You-Go VM instance, you can save a lot by shutting it down when you don't need it. Is there any advantage to doing that with a reserved instance? It's not like the term of the reservation is extended, is it? As I understand it, you're paying for the same fixed period of time whether the VM is running or not.

5 Replies
best response confirmed by Peter Yasuda (Occasional Contributor)

That is correct sir. The reservation is for a fixed time period. You have the option to choose from one or three years upon purchase. The reservation time period starts ticking away just as soon as you purchase it. This is not dependent if you have that specific VM size provisioned or not. You can track the utilization of the reserved instance from the overview page within the portal. So the long winded answer is shutting down the VM's when they are not in use will not extend your reserved instance time. This also applies to CSP software subscriptions.  @Peter Yasuda 

@Bryan Haslip Does shutting down on reserved instance (3 year) save on compute or any other costs or is logging out sufficient? I am just wondering how shutting down can affect overall costs not the length of the subscription.

If you shut down a VM using the Azure Portal - you deallocate the VM, so its not consuming any CPU/Memory resources on a host, if you log off/shut down in Windows, it still runs and reserves host resources, so still costs money.
Reserved Instances are only for Compute, you still get charged for network/disk.
There's no savings on compute. It's possible you could save on data transfer or disk operations, but the amount would be tiny.