Application Gateway Components
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1h 23m

This course will provide you with a foundational understanding of the different ways you can load balance traffic in Microsoft Azure. It includes guided walk-throughs from the Azure platform to give you a practical understanding of how to implement load balancing in your Azure environments.

We start by introducing the different types of load balancers, their components, and their use cases. You'll learn how to deploy a load balancer on Azure. Then we'll dive into Application Gateway and you'll learn about its features and components. You'll also learn about Azure Front Door and how to create a Front Door instance.

We'll then take a look at Web Application Firewall, when it's used, and how to use it in conjunction with Application Gateway, Azure Front Door, and Azure CDN. Finally, you'll learn about Traffic Manager, how it works, and when to use it, as well as how to create a Traffic Manager profile.

Learning Objectives

  • Get a solid understanding of load balancing on Azure
  • Deploy a load balancer
  • Understand the features and components of Application Gateway and how to deploy it
  • Learn about Azure Front Door and how to create a Front Door instance
  • Learn about Web Application Firewall and how to deploy it on Application Gateway
  • Learn how to use Traffic Manager and how to create a Traffic Manager profile

Intended Audience

This course is intended for those who wish to learn about the different ways of performing load balancing in Azure.


To get the most out of this course, you should have a basic understanding of the Azure platform.


Welcome to application Gateway components. Now that you’ve been introduced to application Gateway and what it offers, let’s take a look at the difference components that make up the application Gateway.

The application Gateway consists of front-end IP addresses, listeners, request routing rules, HTTP, settings, backend pools, and health probes.

As is the case with load balancers, an application gateway has a front-end IP address associated with it. The front-end IP address can be public, private, or both. An application Gateway can support one public IP address or one private IP address.

Listeners are used to check for incoming connection requests to the gateway. When you configure a listener, you can specify a protocol, a port, a hostname, and an IP address. If an incoming request matches what has been configured in the listener, the listener accepts the request. The gateway will then route the request to whatever backend members are configured in the rule.

Speaking of rules, request routing rules are used to determine how to route traffic on the listeners. The request routing rule is essentially the glue that binds the listener, the backend pool, and the backend HTTP settings. What the rule does is pretty simple. It takes a request that has been accepted by the listener and forwards that request to the backend. The request routing rule defines which backend server pool that requests should be sent to.

The HTTP settings include ports and protocols that are used to determine whether or not the traffic between the application Gateway and the backend servers is encrypted or not. HTTP settings also determine whether or not cookie-based session affinity should be used to keep a specific user session on the same server.

The backend pools that I have mentioned can consist of NICs, VM scale sets, public IP addresses, internal IP addresses, FQDNs, and multitenant backends like App Service. Backend pools are essentially that - pools of resources that the gateway can direct traffic to.

Lastly, the health probes are used to monitor the health of the resources contained within the backend pool. When an unhealthy resource is detected by the health probe, that resource is removed from service. The health probe will then continue monitoring the unhealthy resource. If it becomes healthy again, the resource is added back to the pool automatically.

To learn more about the azure application gateway components, visit the URL that you see on your screen.

Join me in the next lesson, where I’ll show you how to deploy an application gateway.


About the Author
Learning Paths

Tom is a 25+ year veteran of the IT industry, having worked in environments as large as 40k seats and as small as 50 seats. Throughout the course of a long an interesting career, he has built an in-depth skillset that spans numerous IT disciplines. Tom has designed and architected small, large, and global IT solutions.

In addition to the Cloud Platform and Infrastructure MCSE certification, Tom also carries several other Microsoft certifications. His ability to see things from a strategic perspective allows Tom to architect solutions that closely align with business needs.

In his spare time, Tom enjoys camping, fishing, and playing poker.