Introduction

In today’s dynamic threat environment, security is a primary concern for organizations. One way to secure your network is by using Azure Firewall. Azure Firewall is a fully managed, cloud-based network security service that helps protect your network from threats by filtering inbound and outbound traffic. In this tutorial, we will walk you through the process of implementing Azure Firewall to secure your network.

Prerequisites

Before we start, ensure that you have the following:

• Basic knowledge of Azure Networking
• An Azure subscription with permissions to create resources
• A Virtual Network (VNet) with at least one subnet

Step 1: Create a new Azure Firewall

The first step in securing your network using Azure Firewall is to create a new Azure Firewall. To create a new Azure Firewall, follow these steps:

1. Sign in to the Azure Portal with your account credentials.
2. In the left-hand menu, click on “Create a resource”.
3. Search for “Azure Firewall” and click “Create”.
4. In the “Basics” tab, fill out the required fields such as Subscription, Resource Group, Firewall Name, Region, and Availability zone.
5. Choose “Standard” as the SKU tier for added functionality.
6. Click on “Next: IP Configurations”.

Step 2: Create an IP Configuration

The second step is to create an IP configuration for your Azure Firewall. This IP configuration is used to configure the internal IP address settings for the Azure Firewall. To create an IP configuration, follow these steps:

1. In the “IP Configurations” tab, click on “Add”.
2. Fill out the required fields such as Name and Subnet.
3. Under Public IP address settings, select “Create new”.
4. Fill out the required fields such as Name, SKU, and Static or Dynamic allocation.
5. Click on “Review + create”.
6. Review the details of your Azure Firewall and click on “Create” to provision your new Azure Firewall.

Step 3: Create Firewall Rules

The third step is to create firewall rules to allow or deny traffic to and from your network. Firewall rules are used to define what types of traffic are allowed or blocked. To create a firewall rule, follow these steps:

1. In the Azure Portal, navigate to the newly created Azure Firewall and click on “Firewall Rules” from the left-hand menu.
2. Click on “Add” to create a new firewall rule.
3. Fill out the required fields such as Name, Priority, and Rule Type.
4. Under Source, select “Address Space” and enter the source IP address range that you want to allow or deny traffic to and from. You can also select “Virtual Network” or “IP Group” depending on your need.
5. Under Destination, select “Address Space” and enter the destination IP address range that you want to allow or deny traffic to and from. You can also select “Virtual Network” or “IP Group” depending on your need.
6. Under Protocol, select the protocol that you want to allow or deny traffic for such as TCP, UDP, or Any.
7. Under Action, select “Allow” or “Deny” depending on what you want to do with the traffic.
8. Specify the rule name and description.
9. Click on “Review + create”.
10. Review the details of your firewall rule and click on “Create” to create your new firewall rule.

You can create multiple firewall rules to suit your organization’s needs.

Step 4: Configure Network Rules

The fourth step is to configure network rules to allow or block traffic to and from your network. Network rules are used to define what types of traffic are allowed or blocked between specific IP addresses. To create a network rule, follow these steps:

1. In the Azure Portal, navigate to the newly created Azure Firewall and click on “Network Rules” from the left-hand menu.
2. Click on “Add” to create a new network rule.
3. Fill out the required fields such as Name, Priority, and Rule Type.
4. Under Source, select “IP Addresses” and enter the IP address that you want to allow or deny traffic to or from. You can also select “Virtual Network” or “Service Tag” depending on your need.
5. Under Destination, select “IP Addresses” and enter the IP address that you want to allow or deny traffic to or from. You can also select “Virtual Network” or “Service Tag” depending on your need.
6. Under Protocol, select the protocol that you want to allow or deny traffic for such as TCP, UDP, or Any.
7. Under Action, select “Allow” or “Deny” depending on what you want to do with the traffic.
8. Specify the rule name and description.
9. Click on “Review + create”.
10. Review the details of your network rule and click on “Create” to create your new network rule.

You can create multiple network rules to suit your organization’s needs.

Step 5: Associate Firewall with VNet and Subnet

Now that you have created your Azure Firewall, firewall rules, and network rules, the next step is to associate your Azure Firewall with your Virtual Network and Subnet. To do this, follow these steps:

1. In the Azure Portal, navigate to the newly created Azure Firewall and click on “Firewall Manager” from the left-hand menu.
2. Click on “Virtual networks” and click on “Connect”.
3. Select the Virtual Network that you want to associate with your Azure Firewall.
4. Select the Subnet that you want to associate with your Azure Firewall.
5. Click on “Associate” to connect your Azure Firewall to your Virtual Network and Subnet.

Step 6: Test your Firewall

The final step is to test your Azure Firewall to ensure that it is working correctly. To test your Azure Firewall, follow these steps:

1. In the Azure Portal, navigate to the newly created Azure Firewall and click on “Public IP addresses” from the left-hand menu.
2. Note down the Public IP address of your Azure Firewall.
3. SSH or RDP into a VM in your Virtual Network.
4. Open a web browser and navigate to a website. You should not be able to access the website.
5. Create a firewall rule to allow outbound traffic on port 80 for your VM to the Internet.
6. Refresh the website on your web browser. You should now be able to access the website.

Congratulations! You have successfully implemented Azure Firewall to secure your network.

Conclusion

Azure Firewall is a powerful tool that provides network security to your organization. By following the steps outlined in this tutorial, you can implement Azure Firewall to enhance your organization’s network security posture. Remember to review your firewall and network rules regularly to ensure they are updated and providing the best protection.