Save Costs with Basic SKU Application Gateway for more features and less fixed costs

Hi All!

If you are one of the customers looking to save Costs with Application Gateway for better features than v1 SKU with limited applications as backend pools, here is a post for you!

The Azure Application Gateway Basic SKU is an excellent choice for customers who have applications with lower traffic and do not necessitate high Service Level Agreements (SLAs). This feature is currently in public preview. It's a cost-effective solution that still provides core application-level load balancing features, such as URL-based, host-based, and multi-site routing, as well as cookie-based affinity. This SKU supports a variety of flexible backends, including Azure Kubernetes Service (AKS), Virtual Machine Scale Sets (VMSS), App Services, and on-premises deployments. With built-in high availability and support for HTTP2/HTTPS and WebSocket protocols, the Basic SKU ensures reliable application delivery without the need for advanced traffic management features. For small to medium-sized enterprises or developers seeking a balance between functionality and cost, the Azure Application Gateway Basic SKU presents a compelling option.

Let’s delve into the details of the Azure Application Gateway Basic SKU. This SKU is designed for applications with lower traffic and SLA requirements, and it doesn’t require advanced traffic management features.

Here are the key points:

Advantages of Basic SKU:

1. Basic SKU Features:

   • High Availability: The Basic SKU includes built-in high availability.
   • Protocol Support: It supports HTTP2/HTTPS and WebSocket protocols.
   • Load Balancing: Core application-level load balancing features include URL-based, host-based, and multi-site routing, along with cookie-based affinity.
   • Key Vault integration capabilities
   • Header Rewrite

2. Comparison with Standard V2 SKU:

   • Performance: The Basic SKU is suitable for smaller workloads with a restriction on the number of backend pools supported upto 5 and also supports zone redundancy, while the Standard V2 SKU offers higher performance, autoscaling, zone redundancy, private application gateway, private link, mTLS and static VIPs.
   • Autoscaling: The Standard V2 SKU allows autoscaling based on changing traffic patterns, whereas the Basic SKU doesn’t offer autoscaling.
   • Static VIP: Basic SKU exclusively supports static VIPs, ensuring the VIP associated with the application gateway remains unchanged throughout its lifecycle.
   • URL Rewrite: Only Standard V2 SKU allows you to add, remove, or update an URL.
   • Security: When there is a need to use Web Application Firewall, it is better to choose WAF V2 SKU over Basic  SKU as Basic SKU Application Gateway doesn't support Web Application Firewall yet.

3. When to Use Basic SKU:

   • Lower Traffic Workloads: Choose the Basic SKU for applications with lower traffic.
   • Cost Savings: If advanced features aren’t necessary, Basic SKU provides cost savings.
   • Zone Redundancy: If you need zone redundancy only for limited number of applications served as backends, choose the Basic SKU but if you need zone redundancy along with autoscaling, consider Standard V2 SKU.

Limitations of Basic SKU:

Now let’s explore the limitations of the Azure Application Gateway Basic SKU:

1. Limited Performance:

   • The Basic SKU is designed for smaller workloads and has lower performance compared to the Standard V2 SKU. If your application requires high throughput or autoscaling, consider the Standard V2 SKU instead.

2. No Autoscaling:

   • Unlike the Standard V2 SKU, the Basic SKU does not support autoscaling based on changing traffic patterns. You’ll need to manually adjust capacity if traffic increases.

3. Fewer Advanced Features:

   • The Basic SKU lacks some advanced features available in Standard V2, such as URL rewrite capabilities, private application gateway, private link, Web Application Firewall and mTLS (Mutual TLS Authentication).

Remember to choose the SKU that aligns with your application’s requirements and budget. 

Differences between feature support with Basic SKU and Standard V2 SKU Application Gateway

The following table displays a comparison between Basic and Standard_v2.

¹Estimated based on using an RSA 2048-bit key TLS certificate.

Here is the source from where I got the differences between Basic SKU and Standard V2 SKU Application Gateway Capabilities.

Additional information/resources:

If you want to try Basic SKU in your lower environments for testing while it is in public preview, please use this article to proceed with the steps to register for the Basic SKU feature in public preview. While preview features are not something we recommend customers to use in production environment, consider production-ready Standard V2 SKU Application Gateway for production workloads. For more information on when the Basic SKU Application Gateway feature will be generally available (GA), stay tuned to Azure Updates.

Savings with fixed costs on Application Gateway Basic SKU:

[I have a Basic SKU Application Gateway with a single backend which is an app service in the East US region with zone redundancy enabled.]

Standard SKU Application Gateway Fixed Cost:

[ I have a Standard SKU Application Gateway with a single backend which is an app service in the East US region with zone redundancy enabled.]

For more information on Pricing details and calculations, please check Application Gateway Pricing | Microsoft Azure.

If you want to understand the way pricing is done based on the metrics on an Application Gateway, please check this article.

How to register for preview feature Basic SKU Application Gateway using Azure CLI: 

https://learn.microsoft.com/en-us/azure/application-gateway/overview-v2#register-for-the-preview 

I hope you found this information useful. 

Happy reading!

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