How to Set Up Azure Point-to-Site VPN

Creating a Secure Azure Point-to-Site VPN Connection to Azure Networks

In today’s digital landscape, ensuring secure and reliable access to cloud resources is paramount. For organisations leveraging Microsoft Azure, establishing a secure connection to Azure networks is crucial. In this blog post, we’ll explore how to set up an Azure Point-to-Site VPN using the Azure VPN Gateway. This method is particularly beneficial for users who are not consistently on the corporate network and may not have traditional VPN access.

What is Azure VPN Service?

The Azure VPN Service is a comprehensive solution that allows you to connect your on-premises networks to Azure securely. It supports both Site-to-Site (S2S) and Point-to-Site (P2S) VPN connections, providing flexibility for different networking needs. The service uses industry-standard protocols such as IPsec and IKE to ensure data is encrypted and secure during transit. With Azure VPN, you can extend your on-premises network into the cloud, enabling seamless and secure access to your Azure resources.

What is Azure Point-to-Site VPN?

A Point-to-Site VPN allows individual devices to connect to an Azure Virtual Network (VNet) from anywhere, providing secure access to resources in the cloud. This is ideal for remote workers, travelling employees, or users in various locations who need to access the corporate network securely.

Step-by-Step Guide to Configuring an Azure Point-to-Site VPN

1. Setting Up the VPN Gateway

To begin, you’ll need to configure the VPN Gateway in your Azure environment. This involves creating a new VPN Gateway instance or using an existing one. Navigate to the Azure portal and locate your VPN Gateway.

2. Configuring the Address Pool

Next, configure the address pool that will be assigned to the devices connecting via the Azure Point-to-Site VPN. This address pool is essential as it defines the range of IP addresses that will be allocated to the connecting devices.

IP Addressing Considerations

When configuring the address pool, it’s crucial to consider the existing network infrastructure to avoid IP address conflicts. Here are some key points to keep in mind:

• Non-Overlapping IP Address Spaces: Ensure that the IP address range you assign to the Azure Point-to-Site VPN does not overlap with any existing on-premises or Azure network ranges. Overlapping IP addresses can cause routing issues and connectivity problems¹.
• RFC 1918 Addresses: Use private IP address ranges as defined by RFC 1918 (e.g., 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16). These ranges are reserved for private networks and help avoid conflicts with public IP addresses¹.
• Subnet Sizing: Plan the size of your subnets carefully. Avoid creating excessively large subnets that waste IP address space. Conversely, ensure subnets are large enough to accommodate all potential devices¹.
• Reserved IP Addresses: Be aware that Azure reserves five IP addresses within each subnet for internal use. Factor these reserved addresses into your subnet planning¹.
• IPv6 Considerations: If your organisation is running out of IPv4 addresses, consider using IPv6. Azure supports dual-stack configurations, allowing both IPv4 and IPv6 addresses¹.

3. Integrating with Azure Active Directory (AAD)

For enhanced security and seamless user experience, integrate the Azure Point-to-Site VPN with Azure Active Directory (AAD). This allows users to authenticate using their AAD credentials, providing a secure single sign-on (SSO) experience. Select the OpenVPN option and configure it with your tenant ID and other necessary details.

4. Granting Administrator Consent

Granting administrator consent is a critical step to ensure that the VPN application has the necessary permissions to function correctly. This involves navigating to the Azure Active Directory section in the Azure portal, selecting the Enterprise applications, and then locating the VPN application. Once found, you need to grant admin consent for the required permissions. This step ensures that the application can authenticate users and access the necessary resources.

5. Downloading and Configuring the VPN Client

After configuring the VPN Gateway, the next step is to download the VPN client configuration. This configuration file contains the necessary settings for the VPN client to connect to the Azure network. Once downloaded, extract the files and import them into your VPN client tool. This tool, which can be downloaded from the Azure portal, will facilitate the connection to the Azure network. Ensure that you follow the instructions provided to correctly import the configuration files.

6. Connecting to the Azure Network

With the VPN client configured, you can now initiate the connection. Open the VPN client tool and select the imported configuration. When prompted, authenticate using your AAD credentials. This step ensures that only authorised users can access the network. Upon successful authentication, you will have a secure connection to your Azure VNet. This connection is encrypted, ensuring that data transmitted between your device and the Azure network is secure.

7. Testing the Connection to your Azure Point-to-Site VPN

To verify the connection, perform a few tests. For instance, you can ping a virtual machine (VM) within the Azure network to check connectivity. Additionally, use Remote Desktop Protocol (RDP) to connect to a VM. These tests ensure that the connection is established and functioning correctly. If you can successfully ping and RDP into the VM, it confirms that the VPN connection is working as expected. This step is crucial to ensure that users can access the necessary resources without any issues.

Benefits of Using an Azure Point-to-Site VPN

• Flexibility: Users can connect from anywhere, making it ideal for remote work.
• Security: Utilises AAD for authentication, ensuring secure access.
• Scalability: Easily scales to accommodate a growing number of users without significant infrastructure changes.
• Cost-Effective: Reduces the need for expensive on-premises hardware and maintenance.
• Reliability: Provides a stable and consistent connection to Azure resources.
• Ease of Use: Simple configuration and seamless integration with existing Azure services.

How Azure Point-to-Site VPN Service Fits into a Standard CAF Network Topology

The Cloud Adoption Framework (CAF) provides a structured approach to cloud adoption, ensuring that all aspects of the cloud journey are covered. The Azure VPN Service plays a crucial role in a standard CAF network topology, particularly in the following ways:

1. Hub-and-Spoke Topology: In a hub-and-spoke network topology, the VPN Gateway is typically deployed in the hub network. This centralises network management and security, allowing spokes (individual VNets) to connect securely to the hub. The VPN Gateway facilitates secure communication between on-premises networks and Azure VNets¹.
2. Hybrid Connectivity: Azure VPN Service supports hybrid connectivity by enabling secure connections between on-premises networks and Azure. This is essential for organisations that need to maintain some workloads on-premises while leveraging the cloud for others¹.
3. Transitive Routing: The VPN Gateway can be used in conjunction with Azure ExpressRoute to provide transitive routing. This allows traffic to flow securely between on-premises networks, Azure VNets, and other cloud environments².
4. Security and Compliance: By integrating with Azure Active Directory, the VPN Service ensures that only authenticated and authorised users can access the network. This enhances security and helps meet compliance requirements¹.
5. Scalability and Performance: The Azure VPN Service is designed to handle high volumes of traffic and can scale to meet the demands of large organisations. This ensures that the network remains performant even as the number of connected users grows.

Conclusion

Setting up a Azure Point-to-Site VPN connection to Azure networks is a straightforward process that significantly enhances the security and accessibility of your cloud resources. By following the steps outlined above, you can ensure that your users have secure, reliable access to the Azure environment, regardless of their location.

For more detailed instructions and additional configuration options, refer to the official Azure documentation.

By following these steps, you can create a robust and secure connection to your Azure networks, ensuring that your organisation’s resources are accessible and protected. If you have any questions or need further assistance, feel free to reach out.