Azure VPN Gateway Best Practices
This document outlines best practices for deploying, configuring, and managing Azure VPN Gateways to ensure optimal performance, security, and reliability.
1. Planning and Design
1.1. Choose the Right SKU
Selecting the appropriate VPN Gateway SKU is crucial for meeting your performance, throughput, and feature requirements. Consider:
- Throughput: Determine the expected bandwidth for your site-to-site or point-to-site connections.
- Number of Connections: Evaluate the number of tunnels required for your network topology.
- Features: Some SKUs offer advanced features like BGP, active-active configurations, or IKEv2 support.
Refer to the Azure VPN Gateway SKU documentation for detailed comparisons.
1.2. Plan Your IP Addressing
Ensure that your on-premises network IP address ranges do not overlap with your Azure Virtual Network (VNet) address space. Overlapping ranges can lead to connectivity issues.
1.3. High Availability and Redundancy
For critical workloads, consider implementing:
- Active-Active VPN Gateway: Deploy two gateway instances in an active-active configuration to ensure continuous connectivity if one instance fails.
- Zone-Redundant Gateway SKUs: These SKUs provide resilience against zone failures within a region.
- Redundant Connections: Establish multiple connections between your on-premises network and Azure, potentially to different Azure regions.
2. Configuration and Deployment
2.1. Use BGP for Dynamic Routing
Border Gateway Protocol (BGP) is recommended for managing routing between your on-premises network and Azure. It simplifies route propagation and provides flexibility.
Ensure your on-premises VPN devices support BGP and are configured correctly.
2.2. Secure Your Connections
- IPsec/IKE Parameters: Use strong encryption and integrity algorithms (e.g., AES256, SHA256) and appropriate Diffie-Hellman groups.
- Pre-shared Keys: Use strong, unique pre-shared keys for each connection. Consider using certificate-based authentication for enhanced security.
- Network Security Groups (NSGs): Apply NSGs to the gateway subnet to control traffic flow.
2.3. Configure Point-to-Site VPN
For remote access, configure Point-to-Site (P2S) VPN. Ensure users download and install the correct VPN client configuration packages generated by Azure.
Support for IKEv2 and SSTP protocols is available. Choose the protocol that best suits your client operating systems and network environment.
3. Monitoring and Management
3.1. Monitor Gateway Performance
Regularly monitor key metrics for your VPN Gateway, including:
- Tunnel status
- Data in/out (throughput)
- Packet loss
- Latency
Utilize Azure Monitor and connection diagnostics for insights into your VPN Gateway's health and performance.
3.2. Stay Updated
Azure periodically releases updates and new features for VPN Gateway. Keep your gateway software and on-premises VPN devices updated to benefit from the latest security patches and performance enhancements.
3.3. Logging and Auditing
Enable diagnostic logging for your VPN Gateway to track connection events, configuration changes, and potential security incidents. This is crucial for troubleshooting and auditing purposes.
4. Advanced Scenarios
4.1. ExpressRoute Coexistence
Azure VPN Gateway can coexist with ExpressRoute. This allows for a hybrid connectivity solution, using ExpressRoute for high-bandwidth, low-latency traffic and VPN Gateway for backup or specific workloads.
4.2. Transit Routing
If you have multiple VNets connected via a hub-spoke topology, consider enabling transit routing on your VPN Gateway to allow traffic to flow between spoke VNets through the hub VNet.
By following these best practices, you can build a robust, secure, and efficient VPN solution for your Azure environment.