Azure Spot Virtual Machines: Save Costs with Interruptible Workloads Introduction

When it comes to cost optimization, present cloud computing scenarios are of vital concern to businesses and developers. Although Azure services cater to a great variety of needs, there is one feature that stands out in saving costs: the Azure Spot Virtual Machines, which enables you to run workloads at a fraction of the cost of regular pay-as-you-go Azure Virtual Machines.

In this blog, we are going to explore what Azure Spot VMs are, how they work, and how you can take advantage of them to drastically cut your costs. If interested in mastering cloud computing and cutting costs, consider registering for a cloud computing course in Hyderabad, from where you will understand how to deploy cloud workload effectively and effectively optimize it.

What Are Azure Spot Virtual Machines?

Azure Spot VMs offer an ultra cost-effective option to compute in Azure to run workloads on unused Azure compute capacity at a significantly lower rate than regular pay-as-you-go-VMs. However, the big trade-off here is that these VMs are interruptible—Azure can evict them if it needs the capacity for other workloads, typically with very little notice.

Despite the fact that Azure Spot VMs may be interrupted, they can be an awesome way of saving costs for workloads that do not necessarily require constant uptime or cannot be simply interrupted.

How do Azure Spot VMs work?

Azure Spot VMs will make use of spare capacity that is idle in Microsoft Azure's data centers. These instance allocations happen only when unused capacity is available, and are priced lower than regular VMs so users are encouraged to run non-critical workloads at these times.

Eviction Policy: Azure has the right to evict Spot VMs with short notice in case the demand for capacity increases. Usually, you receive a warning of about 30 seconds before your VM is thrown out. You have a choice of dealing with eviction through automated processes such as restarting or migrating your workloads to another VM.

Pricing Model: Spot VMs are priced based on available capacity, so the price can vary. In fact, at times the price can get to be a fraction of what one would pay for regular cost. Prices are set by Azure based on supply and demand for compute resources.

Use Cases: Spot VMs are great for fault-tolerant workloads that can be interrupted. Examples include:

Batch processing

Rendering and simulations

Dev and test environments

Big data analytics

Benefits of Azure Spot VMs

Azure Spot VMs provide some key benefits but are mostly defined by cost, although flexibility and scalability are also other benefits:

1. Huge Cost Savings

The most attractive feature of Azure Spot VMs is the cost. Azure offers these instances at a steep discount sometimes up to 90 percent compared to standard Azure VMs. This makes Spot VMs an ideal choice for businesses looking to save money on workloads that aren't mission-critical.

Best Practice: Use Azure Spot VMs for non-production environments or batch jobs that can tolerate interruptions.

2. Integrate Silently with Azure Services

Spot VMs integrate seamlessly with other Azure services, such as Azure Kubernetes Service (AKS) and Virtual Machine Scale Sets (VMSS). This means you can scale your applications dynamically and automatically at a low cost and accordingly adjust resources based on demand.

Best Practice: Use Azure VM Scale Sets to automatically deploy and manage Spot VMs within your larger infrastructure.

3. Flexibility in Pricing and Size

Azure provides several sizes of VMs for the Spot VM, where you can choose the best one to support your workload. There's flexibility in the pricing model, and the pricing depends on these factors: region, size of VM, and present capacity.

Best Practice: Periodically monitor Spot VM prices to refine your savings strategy and scale your resources based on requirement.

4. Automated Eviction Handling

You can find features in Azure that automate responses to Spot VM evictions. Either through eviction policies or workload migrations, you would be prepared to minimize impact when your Spot VM gets evicted.

Best Practice: Leverage Azure Automation and Azure Logic Apps for automatic eviction handling and minimizing intervention.

How to Use Azure Spot VMs

Setting up and using Azure Spot VMs is simple. Here's a step-by-step guide to get you started:

Step 1: Create a Virtual Machine with Spot Pricing

Sign in to the Azure Portal .

Go to Create a resource > Compute > Virtual Machine .

Fill in all the required details, such as subscription, resource group, region, and VM image.

From the Size pane, select a VM size and click under the Pricing pane on the Spot button.

Specify your Eviction Policy-you have two options: automatically delete the VM upon eviction or retain the VM in a deallocated state.

Review the settings and click on Create to deploy the Spot VM.

Step 2: Automate the scaling of Spot VMs with Azure Scale Sets

Azure Spot VMs can be scaled automatically with Azure Virtual Machine Scale Sets (VMSS). This includes setting the desired number of instances and then overseeing Spot VM availability.

Under Compute, click Create a resource > Virtual Machine Scale Set.

In Instance details, select the Spot option.

Configure scale parameters such as minimum, maximum, and target instance counts.

Create scaling rules as per your workload requirement.

Select Create to create the VMSS with Spot pricing.

Step 3: Monitor and Manage Costs

To ensure you maximize use of your Spot VMs, use Azure Cost Management to monitor usage and pricing on your Spot instances, so you can gauge where you're spending your money and when you may need to adjust to a changing price.

Best Practices for Using Azure Spot VMs

Best Practices for Getting the Most Benefit from Azure Spot VMs with Minimal Disruptions:

1. Use Spot VMs for Stateless or Fault-Tolerant Workloads

Use Spot VMs for applications or workloads that are stateless or can tolerate interruptions, such as batch jobs, testing environments, or big data analytics. Avoid the use of Spot VMs in production applications or workloads demanding high availability.

2. Configure Auto Scaling with Azure VMSS

One great way to dynamically scale your Spot VMs is by using Azure Virtual Machine Scale Sets, particularly when the demand for compute resources is fluctuating. By configuring the scale sets to include both regular VMs and Spot VMs, you help balance cost savings with greater availability.

3. Automate Responses to Eviction

Prepare for Spot VM evictions by automating workload migration to alternative VMs or regions. Azure offers tools such as Azure Automation and Azure Logic Apps to ensure that evictions from a VM minimize downtime.

4. Monitor Price Fluctuations

As Spot VM prices can vary depending on available capacity, it’s essential to monitor price changes to make cost-effective decisions. Tools like Azure Cost Management can help you track and adjust your usage based on current prices.

Conclusion

Azure Spot VMs offer a remarkable opportunity to reduce costs on the cloud, especially for workloads with a tolerant nature for interruption. Using the unused capacity of compute by Azure at significantly reduced prices can help businesses save on expenses without compromising performance for non-critical tasks.

If you are interested in knowing more on cloud computing, cost-saving strategies, and managing workloads in Azure, a course on cloud computing in Hyderabad will give you all the knowledge and skills required to have the best out of Azure's services, such as Spot VMs.