Application Gateway needs Load Balancer?

Question

Our infrastructure for our web application needs to be compliant with the following security requirement.

For public-facing web applications, new threats and vulnerabilities are addressed on an ongoing basis and these applications are protected against known attacks

For this purpose, in front of our App Service we are deploying an Application Gateway that will have its Firewall and DDOS protection enabled. As part of this deployment, we need to create a Public IP for our Application Gateway.

Can this Public IP become a bottleneck for our incoming requests? Shouldn't we deploy a Load Balancer in front of this Public IP to handle traffic?

Answer 1

@Santiago Marrone

Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.

I understand that you would like to know how the best practices for Load Balancing.

Please note :

• An Application gateway itself is a Load Balancer.
  • See : Load-balancing options
• The Public IP of the Application Gateway will not be a bottleneck.
  • No Public IP in Azure is a bottleneck. Instead, the service to which it is associated may become Bottleneck.

In your case, it is App Gateway.

• You must configure the App Gateway so that it is perfectly capable of handling the requests.
• This can be achieved by configuring the number of App gateway instances
  • The more the instances, the more load it can handle.
• Please consider using Scaling options in Azure App Gateway

With autoscaling enabled, the Application Gateway and WAF v2 SKUs scale out or in based on application traffic requirements. This mode offers better elasticity to your application and eliminates the need to guess the application gateway size or instance count. This mode also allows you to save cost by not requiring the gateway to run at peak-provisioned capacity for expected maximum traffic load.

See : How Autoscaling of App Gw provides High Availability to your application

Please let us know if we can be of any further assistance here.

Thanks,

Kapil

---

Please Accept an answer if correct. Original posters help the community find answers faster by identifying the correct answer.