Microsoft introduce Azure Spot Virtual Machines

Microsoft have announced the preview of Azure Spot Virtual Machines – to replace the current preview of Azure low-priority Virtual Machines, which will be retired January 1, 2020.

What are Spot instances?

They’ve been around for several years, particularly prominent in the world of Amazon AWS. They provide access to unused resources within a cloud datacentre at a significant discount – but the resources can be recalled by the datacentre provider almost immediately. Microsoft use the term “evicted” and your VMs can be evicted in one of two scenarios:

• Azure needs its capacity back
• The current price exceeds the maximum you’re willing to pay*

*More on that shortly

If you subscribe to scheduled events, you’ll get a 30-second warning prior to a Spot machine being evicted.

When are they a good option?

The fact that Spot Virtual Machines can stop running with almost no notice clearly means the don’t make sense in every case, but there are certain scenarios where they can work very well such as:

• Big Data
• Containers
• Testing environments
• High Performance Computing (HPC)
• Sale-out additional capacity

Anything where one (or more) VMs suddenly going offline won’t cause a huge issue. Either a workload that can continue with reduced resources (albeit more slowly) and/or a workload that can simply pick up where it left off later on.

Pricing for Azure Spot VMs

Pricing will be variable depending on the available capacity of your chosen VM in that Azure region, and the current prices will be available to see within the Azure portal – as per this screenshot from the Microsoft announcement:

Google say you can reach discounts of up to 80% while Amazon & Microsoft both claim up to 90%.

Is this an ITAM thing?

Absolutely yes – to a degree.
Spot virtual machines can be a great way of reducing virtual machine costs in the cloud (not just in Azure) when used in the right places. In so many areas, effective management of cloud requires a more intimate knowledge and understanding of what your business is doing with its technology stack – and effective use of Spot instances is another great example.
The deployment and management of Spot instances is, of course, the purview of another team – but working to ensure your cloud cost strategy is fully optimised is all ITAM!
As an initial step, I’d suggest:

• Look at where, and how, your business uses cloud
• Identify potential spot scenarios
• Meet with the relevant teams & agree where spot instances could be used
• Launch project to convert resources to spot VMs – with ITAM oversight
• Monitor for “X” period of time (3-6 months say)
• Present to board as part of ITAM cost savings strategy

Remember, while this is a new announcement from Microsoft, Spot virtual machines already exist with Amazon AWS while Google have “Preemptible VM Instances”.

Further Reading

Microsoft announcement – https://azure.microsoft.com/en-gb/blog/announcing-the-preview-of-azure-spot-virtual-machines/
Microsoft Spot FAQs – https://azure.microsoft.com/en-us/pricing/spot/