Tutorial / Cram Notes
Azure Front Door is a scalable and secure entry point for fast delivery of your global web applications. It combines various traffic routing and load-balancing capabilities to provide high availability and performance for your applications. Azure Front Door works at Layer 7 (HTTP/HTTPS layer) using the split TCP-based anycast protocol to ensure that user traffic is directed to the nearest and most responsive application backend.
Benefits of Azure Front Door
- Increased application performance with anycast protocol and global load balancing
- Instant global failover for high availability
- URL-based routing and Path-Based Redirection
- Session affinity to maintain user sessions on the same backend
- TLS termination allowing you to offload SSL processing from the application layer
- Endpoint health probes and automatic failover
- Security features including Web Application Firewall (WAF)
Setting up Azure Front Door
1. Creation of Azure Front Door
Begin by accessing the Azure portal and searching for Azure Front Door. Then, you’ll select “Create a new Front Door” and subsequently start its setup process:
- Configure the Front Door’s basic settings like subscription, resource group, and instance details.
- Define the Front Door host name that will be the entry point for your users.
2. Define the Front Door Backend Pool
The backend pool holds one or more backend services that could be Azure Web Apps, Cloud Services, or any external service reachable via public Internet:
- Under the Backend Pools section, add each of your application backends.
- Assign priorities and weights if you require active-passive or active-active load balancing.
- Set up health probes to check the status of your backend endpoints.
3. Configure Routing Rules
Routing rules determine how traffic is directed to specific backend pools based on URLs:
- Create a rule that specifies which paths will be forwarded to which backend pools.
- You can also set up URL rewrite and redirection options in this section.
- Configure caching to optimize performance by temporarily storing content closer to users.
4. Enable Session Affinity
If your application requires users to maintain a persistent session with the same backend server, you can turn on session affinity:
- Choose the “Cookie-based affinity” option in the backend pool settings.
- Configure the affinity settings to suit your application requirements.
5. Add Security Features
Protect your web applications by configuring the Web Application Firewall (WAF) in Azure Front Door:
- Define a WAF policy and associate it with your Front Door instance.
- Customize rules and managed rule sets based on the OWASP core rule sets or your own specific requirements.
- Adjust the WAF mode to either “Detection” or “Prevention”.
Example
Imagine setting up Azure Front Door for a global e-commerce platform with backend services in the East US and West Europe. In this example, you would:
- Set up two backend pools: “EastUSBackend” for the East US app service and “WestEuropeBackend” for the West Europe app service.
- Configure a routing rule for the path “/images/*” to a backend pool optimized for static content, with caching enabled.
- Create a WAF policy with custom rules to protect against SQL injection and cross-site scripting, applying this policy to your Front Door.
Summary Table of Key Configurations
| Configuration Element | Description |
| Backend Pools | Holds backend services where requests will be sent. |
| Health Probes | Checks the status of your backend endpoints. |
| Load Balancing | Distributes traffic across different backends. |
| Routing Rules | Defines how incoming traffic should be routed. |
| Caching | Stores content temporarily to improve load times. |
| WAF Policy | Protects web applications from common vulnerabilities. |
By following these steps and considering the example provided, you can create and configure Azure Front Door to enhance the performance and security of your web applications. Keep in mind that Azure Front Door offers a range of features that can be tailored to meet the needs of various scenarios, from basic web hosting to complex, multi-region microservices architectures. Always review and test your configurations to ensure they meet both your performance and security requirements.
Practice Test with Explanation
True or False: Azure Front Door provides autoscaling and instant global failover to maintain application availability.
- True
Answer: True
Explanation: Azure Front Door features autoscaling to handle varying loads and provides instant global failover to maintain high availability of applications.
True or False: You can use Azure Front Door Service only in conjunction with Azure Web Apps.
- False
Answer: False
Explanation: Azure Front Door can route traffic to any internet-facing service, not just Azure Web Apps.
Which of the following is NOT a feature of Azure Front Door?
- A. DDoS protection
- B. Content Delivery Network
- C. Load balancing
- D. Virtual Network Peering
Answer: D. Virtual Network Peering
Explanation: Virtual Network Peering is not a feature of Azure Front Door, as it is a global service that does not rely on virtual network peering but instead distributes network traffic across global points of presence.
What type of rule engine does Azure Front Door use for customizing routing of HTTP/HTTPS traffic?
- A. Web Application Firewall (WAF) rules
- B. Network Security Group (NSG) rules
- C. Front Door Route rules
- D. Traffic Manager profiles
Answer: C. Front Door Route rules
Explanation: Azure Front Door provides a route engine to customize the routing of HTTP/HTTPS traffic using Front Door Route rules.
True or False: Azure Front Door Service only supports IPv4 addressing.
- False
Answer: False
Explanation: Azure Front Door Service supports both IPv4 and IPv6 addressing.
In Azure Front Door, what would you configure to distribute traffic among different service endpoints based on various algorithms?
- A. SSL offloading
- B. Load Balancing
- C. WAF policy
- D. Session affinity
Answer: B. Load Balancing
Explanation: Azure Front Door’s load balancing feature is used to distribute traffic among different service endpoints based on different algorithms or routing methods.
True or False: Azure Front Door does not provide caching capabilities to reduce latency and save bandwidth.
- False
Answer: False
Explanation: Azure Front Door does provide caching capabilities to enhance performance by reducing latency and saving bandwidth.
Which of the following would be a valid reason to use Azure Front Door?
- A. To extend a virtual network across regions
- B. To optimize global routing for your web traffic
- C. To grant private network access to Azure services
- D. To enable automatic virtual machine patching
Answer: B. To optimize global routing for your web traffic
Explanation: Azure Front Door is designed to optimize and manage global routing of web traffic among different regions and data centers.
True or False: Azure Front Door offers URL path-based routing for your content delivery.
- True
Answer: True
Explanation: Azure Front Door offers URL path-based routing, enabling users to map different paths in the user’s URL to different backend pools.
What type of protection against web vulnerabilities and attacks does Azure Front Door offer?
- A. Network Security Group (NSG)
- B. Azure Bastion
- C. Web Application Firewall (WAF)
- D. Azure Firewall
Answer: C. Web Application Firewall (WAF)
Explanation: Azure Front Door offers a Web Application Firewall (WAF) that provides protection against web vulnerabilities and attacks.
When configuring Azure Front Door, which entity is used to group your HTTP/HTTPS load balancing endpoints?
- A. Backend pools
- B. Routing rules
- C. Health probes
- D. Frontdoor designer
Answer: A. Backend pools
Explanation: Backend pools are used in Azure Front Door to group your HTTP/HTTPS load balancing endpoints for the purpose of routing traffic.
True or False: To protect against distributed denial of service (DDoS) attacks, you should configure Azure DDoS Protection in addition to the Azure Front Door service.
- False
Answer: False
Explanation: Although adding Azure DDoS Protection can enhance security, Azure Front Door already includes built-in DDoS protection features. Additional Azure DDoS Protection is generally used to protect other Azure resources.
Interview Questions
What is Azure Front Door?
Azure Front Door is a global, scalable entry point that uses the Microsoft global edge network to create fast, secure, and highly available web applications.
What is the difference between Azure Front Door and Azure Application Gateway?
Azure Front Door is a global load balancing and routing service, while Azure Application Gateway is a web traffic load balancer that enables you to manage traffic to your web applications.
What are the key features of Azure Front Door?
Some key features of Azure Front Door include global routing, traffic acceleration, SSL offload, web application firewall (WAF), and access and identity control.
How can you create an Azure Front Door?
You can create an Azure Front Door by using the Azure portal, Azure PowerShell, Azure CLI, or an ARM template.
What is a backend pool in Azure Front Door?
A backend pool is a collection of backend endpoints that Azure Front Door routes traffic to.
What is a health probe in Azure Front Door?
A health probe is a check performed by Azure Front Door to determine whether a backend endpoint is healthy and available to handle incoming traffic.
What is a frontend endpoint in Azure Front Door?
A frontend endpoint is a specific hostname, domain, or IP address that Azure Front Door listens to and routes traffic to the backend pools.
What is a routing rule in Azure Front Door?
A routing rule specifies the frontend endpoint to match, the backend pool to use, and the load-balancing algorithm to use.
What is SSL offload in Azure Front Door?
SSL offload is the process of terminating SSL/TLS connections at the Azure Front Door edge nodes, which can reduce the computational load on backend servers.
What is a Web Application Firewall (WAF) in Azure Front Door?
A WAF is a security feature that helps protect web applications from common attacks, such as SQL injection, cross-site scripting (XSS), and cross-site request forgery (CSRF).
Can you use Azure Front Door to route traffic to resources outside of Azure?
Yes, Azure Front Door supports routing traffic to resources both within and outside of Azure.
What are the pricing options for Azure Front Door?
Azure Front Door has a pay-as-you-go pricing model, as well as reserved capacity pricing for customers with predictable traffic patterns.
Can you use Azure Front Door to manage traffic to multiple domains?
Yes, Azure Front Door can be used to manage traffic to multiple domains or subdomains.
Can you use Azure Front Door for global load balancing?
Yes, Azure Front Door is designed for global load balancing and can route traffic to the closest available backend endpoint based on the client’s location.
Does Azure Front Door integrate with other Azure services?
Yes, Azure Front Door integrates with other Azure services, such as Azure Traffic Manager, Azure Application Gateway, and Azure CDN.
Thanks for this detailed guide on creating and configuring Azure Front Door!
I’m struggling with setting up custom domains for Azure Front Door. Can anyone help?
Great post! It helped me configure Azure Front Door for my app.
Can someone explain how URL-based routing works in Azure Front Door?
I encountered an issue with SSL certificates. Anyone faced the same?
How do I integrate Azure Front Door with Web Application Firewall for added security?
The steps for configuring the backend pool aren’t clear to me. Has anyone successfully done this?
This blog post is very helpful, thanks!