Azure S2S VPN ARM Template Ready-to-Deploy Reusable Solution
Azure S2S VPN ARM Template Ready-to-Deploy Reusable Solution
Overview
This repository contains a production-ready Azure Resource Manager (ARM) template designed to deploy a complete Site-to-Site (S2S) VPN infrastructure in Microsoft Azure.
The solution enables secure communication between an Azure Virtual Network and an on-premises network via an IPSec VPN tunnel.
The template is fully parameterized and validated using Azure-native testing mechanisms to ensure deployment reliability and consistency across environments.
2. What This Template Deploys
This ARM template provisions the following Azure resources:
Virtual Network (VNet)
Custom address space defined via parameters
Includes required GatewaySubnet
Gateway Subnet
Dedicated subnet named GatewaySubnet
Required for VPN Gateway deployment
Configurable CIDR range
Public IP Address
Standard SKU
Static allocation
Used by the VPN Gateway
Virtual Network Gateway
VPN Gateway (Route-based)
Supports IPSec/IKE (IKEv2 by default)
Configurable SKU (VpnGw1–VpnGw5)
Supports Generation1 and Generation2
Local Network Gateway
Represents on-premises VPN device
Stores public IP and on-prem address spaces
VPN Connection
IPSec tunnel between Azure and on-prem
Uses shared key authentication
Configurable protocol (IKEv1/IKEv2)
Includes Dead Peer Detection (DPD)
3. Architecture Summary
Azure VNet contains a dedicated GatewaySubnet where the VPN Gateway is deployed.
The VPN Gateway connects to an on-premises network via the Local Network Gateway using an IPSec tunnel.
This architecture supports:
Hybrid cloud connectivity
Secure data transfer between environments
Enterprise-grade network integration
4. Prerequisites
Before using this template, ensure the following:
Azure Requirements:
Active Azure Subscription
Contributor or Owner Permissions on the RG
Azure CLI installed or Azure Cloud Shell access
Networking Requirements
Non-overlapping IP Address ranges between Azure and On-Premises Networks
Valid public IP Address for the On-Premises VPN device
Firewall configured to allow:
UDP 500 (IKE)
UDP 4500 (IPSec NAT-T)
Design Requirements
GatewaySubnet must be named exactly GatewaySubnet
Recommended subnet size:
Minimum: /27
Recommended: /26 for scalability
5. Files Included
template.json
Main ARM template defining all Azure resources
parameters.json
Parameter file containing environment-specific values
deploy.ps1
Optional deployment automation script
6. Deployment Instructions
Step 1: Upload Files
Upload template.json and parameters.json to Azure Cloud Shell or local environment.
Step 2: Validate Template
az deployment group validate \
--resource-group RG-ARM-TEMPLATES \
--template-file template.json \
--parameters parameters.json
Step 3: Run WHAT-IF (Recommended)
az deployment group what-if \
--resource-group RG-ARM-TEMPLATES \
--template-file template.json \
--parameters parameters.json
Step 4: Deploy (Optional)
az deployment group create \
--resource-group RG-ARM-TEMPLATES \
--template-file template.json \
--parameters parameters.json
7. Testing and Validation (Completed)
The following validation steps were successfully performed:
Template Validation
JSON Syntax Verified
ARM Schema Compliance Confirmed
Resource Definitions Validated
Parameter Validation
All Parameters Correctly Mapped
Data Types Validated (String, Array, Object, secureString)
No Missing or Mismatched Parameters
Azure WHAT-IF Validation
Azure Control Plane Accepted the Configuration
Resource Dependencies Resolved Correctly
No policy or RBAC Conflicts Detected
No Runtime Validation Errors
Expected Result output:
Resource changes: 5 to create
Resources identified:
Virtual Network
Public IP Address
Virtual Network Gateway
Local Network Gateway
VPN Connection
This confirms the template is:
Deployable
Structurally correct
Azure-compliant
8. Important Notes
VPN Gateway deployment takes approximately 30–45 minutes
VPN connection status will remain NotConnected until a real on-prem device is configured
This template validates infrastructure deployment only, not network connectivity
9. Security Considerations
Shared Key is defined in the Parameters File for Testing Purposes
For Production:
Use Azure Key Vault
Avoid storing secrets in plain text
Rotate keys regularly
10. Limitations
Does not deploy on-prem VPN device
Does not validate tunnel connectivity
Does not include diagnostic settings or monitoring
11. Best Practices Implemented
Full parameterization for reusability
Use of Standard SKU Public IP
Route-based VPN configuration
Explicit dependency management
Tagging support for governance
SecureString usage for sensitive values
12. Conclusion
This ARM template provides a fully validated, enterprise-ready foundation for deploying Azure Site-to-Site VPN infrastructure. All pre-deployment validation steps have been successfully completed using Azure-native tools, ensuring the template can be deployed without errors.
13. Next Steps
Deploy the template in a Test Environment
Configure On-Prem VPN Device
Validate Connectivity and Routing
Extend with Monitoring and Diagnostics
Integrate into CI/CD Pipelines
Support
For questions or custom template requests, please contact:
ITCloudAcademy Support Team
Email: support@ITCloudAcademy.net
Email: info@ITCloudAcademy.net
Website: http://www.itcloudacademy.net
Support Hours:
Monday to Friday
9:00 AM to 6:00 PM MST
