Azure Availability sets – Guide on Overview and Benefits

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Azure Availability Sets is a feature in the Azure cloud computing platform that allows you to distribute your virtual machines (VMs) across multiple physical servers within a data center. This distribution provides a higher level of availability and resiliency by ensuring that your VMs are not all running on a single physical server. In this lesson, we’ll provide an overview of Azure Availability Sets, the benefits they provide, and answer some frequently asked questions. Additionally, we’ll look at some real-world case studies that demonstrate the effectiveness of Availability Sets.

What is an Azure Availability Set?

An Azure Availability Set is a logical grouping of two or more VMs that are deployed across multiple fault domains and update domains. Fault domains are groups of hardware that share a common power source and network switch. Update domains are groups of VMs that are updated and rebooted together during planned maintenance events. By distributing VMs across multiple fault domains and update domains, Azure ensures that there is no single point of failure in the deployment.

Benefits of using Azure Availability Sets

  1. High availability: The primary benefit of Azure Availability Sets is high availability. By distributing VMs across multiple fault domains and update domains, Azure ensures that your application remains available even if one of the fault domains or update domains experiences an outage.
  2. Resiliency: Azure Availability Sets provide a higher level of resiliency than deploying VMs on a single physical server. If one physical server fails, the VMs deployed on that server can be automatically moved to another server in a different fault domain.
  3. Simplified management: By grouping VMs into an Availability Set, you can simplify management tasks such as updating and patching. You can update or patch VMs in an Availability Set one update domain at a time, ensuring that at least one VM is always available.
  4. Cost-effective: Azure Availability Sets can help you reduce your infrastructure costs by allowing you to run multiple VMs on a single physical server. By distributing VMs across multiple fault domains, you can also ensure that your application remains available even during planned maintenance events.

Frequently Asked Questions

How many VMs can I add to an Availability Set?

You can add up to 200 VMs to an Availability Set.

Can I add VMs to an Availability Set after deployment?

Yes, you can add VMs to an Availability Set after deployment.

Can I remove VMs from an Availability Set after deployment?

Yes, you can remove VMs from an Availability Set after deployment.

Can I change the number of fault domains or update domains in an Availability Set after deployment?

No, you cannot change the number of fault domains or update domains in an Availability Set after deployment.

How do I know if my VMs are running in an Availability Set?

You can view the properties of a VM in the Azure portal or use Azure PowerShell or Azure CLI to view the Availability Set information.

Case Studies

  1. GE Healthcare: GE Healthcare uses Azure Availability Sets to ensure high availability and resiliency for its cloud-based medical imaging and analytics platform. The platform processes over 50 million images per year and requires 99.99% uptime to ensure patient safety.
  2. Accenture: Accenture uses Azure Availability Sets to ensure high availability and resiliency for its Accenture myWizard platform, which provides intelligent automation solutions to clients. The platform processes over 20,000 transactions per minute and requires 99.99% uptime to ensure business continuity.

Conclusion

Azure Availability Sets provide a powerful tool for ensuring high availability and resiliency in your Azure infrastructure. By distributing VMs across multiple fault domains and update domains, you can ensure that your application remains available even during planned and unplanned outages. Additionally, Azure Availability Sets can simplify management tasks and reduce infrastructure costs by allowing you to group VMs and run them on a single physical server. If you’re looking to improve the availability and resiliency of your Azure infrastructure, Azure Availability Sets are a great option to consider.