VNet to VNet connectivity between Azure Stack Hub instances with Fortinet FortiGate NVA

This article describes how to connect a VNET in one Azure Stack Hub to a VNET in another Azure Stack Hub using Fortinet FortiGate NVA, a network virtual appliance.

This article addresses the current Azure Stack Hub limitation, which lets tenants set up only one VPN connection across two environments. The article describes how to set up a custom gateway on a Linux virtual machine that allows multiple VPN connections across different Azure Stack Hub. The procedure in this article deploys two VNETs with a FortiGate NVA in each VNET: one deployment per Azure Stack Hub environment. It also details the changes required to set up an IPSec VPN between the two VNETs. The steps in this article should be repeated for each VNET in each Azure Stack Hub.

Prerequisites

  • Access to an Azure Stack Hub integrated system with available capacity to deploy the required compute, network, and resource requirements needed for this solution.

  • A network virtual appliance (NVA) solution downloaded and published to the Azure Stack Hub Marketplace. An NVA controls the flow of network traffic from a perimeter network to other networks or subnets. This procedure uses the Fortinet FortiGate Next-Generation Firewall Single VM Solution.

  • At least two available FortiGate license files to activate the FortiGate NVA. For information about how to get these licenses, see the Fortinet Document Library article Registering and downloading your license.

    This procedure uses the Single FortiGate-VM deployment. The procedure describes the steps to connect the FortiGate NVA to the Azure Stack Hub VNET in your on-premises network.

    For more information about how to deploy the FortiGate solution in an active-passive (HA) set up, see HA for FortiGate-VM on Azure in the Fortinet document library.

Deployment parameters

The following table summarizes the parameters that are used in these deployments for reference:

Deployment one: Forti1

FortiGate Instance Name Forti1
BYOL License/Version 6.0.3
FortiGate administrative username fortiadmin
Resource Group name forti1-rg1
Virtual network name forti1vnet1
VNET Address Space 172.16.0.0/16*
Public VNET subnet name forti1-PublicFacingSubnet
Public VNET address prefix 172.16.0.0/24*
Inside VNET subnet name forti1-InsideSubnet
Inside VNET subnet prefix 172.16.1.0/24*
VM Size of FortiGate NVA Standard F2s_v2
Public IP address name forti1-publicip1
Public IP address type Static

Deployment two: Forti2

FortiGate Instance Name Forti2
BYOL License/Version 6.0.3
FortiGate administrative username fortiadmin
Resource Group name forti2-rg1
Virtual network name forti2vnet1
VNET Address Space 172.17.0.0/16*
Public VNET subnet name forti2-PublicFacingSubnet
Public VNET address prefix 172.17.0.0/24*
Inside VNET subnet name Forti2-InsideSubnet
Inside VNET subnet prefix 172.17.1.0/24*
VM Size of FortiGate NVA Standard F2s_v2
Public IP address name Forti2-publicip1
Public IP address type Static

Note

If the previous names overlap in any way with the on-premises network environment, including the VIP pool of Azure Stack Hub, choose a different set of address spaces and subnet prefixes. Also ensure that the address ranges don't overlap with each other.

Deploy the FortiGate NGFW Marketplace Items

Repeat these steps for both Azure Stack Hub environments.

  1. Open the Azure Stack Hub user portal. Be sure to use credentials that have at least Contributor rights to a subscription.

  2. Select Create a resource and search for FortiGate.

    Screenshot shows a single line of results from the search for fortigate, with the name of found item FortiGate NGFW - Single VM Deployment (BYOL).

  3. Select the FortiGate NGFW and select the Create.

  4. Complete Basics using the parameters from the Deployment parameters table.

    Your form should contain the following information:

    Screenshot shows the text boxes (such as Instance Name and BYOL License) of the Basics dialog box filled in with values from the Deployment Table.

  5. Select OK.

  6. Provide the virtual network, subnets, and VM size details from the Deployment parameters.

    If you want to use different names and ranges, take care not to use parameters that conflict with the other VNET and FortiGate resources in the other Azure Stack Hub environment. This limitation is especially true when setting the VNET IP range and subnet ranges within the VNET. Check that they don't overlap with the IP ranges for the other VNET you create.

  7. Select OK.

  8. Configure the public IP to be used for the FortiGate NVA:

    Screenshot shows the Public IP address name text box of the IP Assignment dialog box shows a value of forti1-publicip1 (from the Deployment Table).

  9. Select OK and then Select OK.

  10. Select Create.

The deployment takes about 10 minutes. You can now repeat the steps to create the other FortiGate NVA and VNET deployment in the other Azure Stack Hub environment.

Configure routes (UDRs) for each VNET

Perform these steps for both deployments, forti1-rg1 and forti2-rg1.

  1. Go to the forti1-rg1 resource group in the Azure Stack Hub portal.

    Screenshot shows the list of resources in the forti1-rg1 resource group.

  2. Select the forti1-forti1-InsideSubnet-routes-xxxx resource.

  3. Select Routes under Settings.

    Screenshot shows the highlighted Routes item of Settings.

  4. Delete the to-Internet route.

    Screenshot shows the highlighted to-Internet route. There is a delete button.

  5. Select Yes.

  6. Select Add.

  7. Name the Route to-forti1 or to-forti2. Use your IP range if you're using a different IP range.

  8. Enter:

    • forti1: 172.17.0.0/16
    • forti2: 172.16.0.0/16

    If you use a different IP range, enter your IP range.

  9. Select Virtual appliance for the Next hop type.

    • forti1: 172.16.1.4
    • forti2: 172.17.0.4

    If you use a different IP range, enter your IP range.

    Screenshot shows the Edit route dialog box for to-forti2 has text boxes with values: Address prefix is 172.17.0.0/16, Next hop type is Virtual appliance, and Next hop address is 172.16.1.4.

  10. Select Save.

Repeat these steps for each InsideSubnet route in each resource group.

Activate the FortiGate NVAs and configure an IPSec VPN connection on each NVA

You need a valid license file from Fortinet to activate each FortiGate NVA. The NVAs can't function until you activate each NVA. For more information about how to get a license file and the steps to activate the NVA, see the Fortinet Document Library article Registering and downloading your license.

You must acquire two license files: one for each NVA.

Create an IPSec VPN between the two NVAs

After you activate the NVAs, create an IPSec VPN between the two NVAs. Follow the steps for both the forti1 NVA and forti2 NVA:

  1. Go to the fortiX VM Overview page to get the assigned public IP address:

    Screenshot shows the forti1 overview page shows the resource group, status, and so on.

  2. Copy the assigned IP address, open a browser, and paste the address into the address bar. Your browser might warn you that the security certificate isn't trusted. Continue anyway.

  3. Enter the FortiGate administrative user name and password you provided during the deployment.

    Screenshot shows the login screen, which has a Login button and text boxes for user name and password.

  4. Select System > Firmware.

  5. Select the box showing the latest firmware, such as FortiOS v6.2.0 build0866.

    Screenshot shows the FortiOS v6.2.0 build0866 firmware has a link to release notes, and two buttons: Backup config and upgrade and Upgrade.

  6. Select Backup config and upgrade and Continue when prompted.

  7. The NVA updates its firmware to the latest build, then reboots. The process takes about five minutes. Log back into the FortiGate web console.

  8. Select VPN > IPSec Wizard.

  9. Enter a name for the VPN, such as conn1 in the VPN Creation Wizard.

  10. Select This site is behind NAT.

    Screenshot of the VPN Creation Wizard shows it to be on the first step, VPN Setup with Site to Site for Template Type, FortiGate for Remote Device Type, and This site is behind NAT for NAT Configuration.

  11. Select Next.

  12. Enter the remote IP address of the on-premises VPN device to which you're going to connect.

  13. Select port1 as the Outgoing Interface.

  14. Select Pre-shared Key and enter (and record) a pre-shared key.

    Note

    You need this key to set up the connection on the on-premises VPN device. The key must match exactly.

    Screenshot shows the VPN Creation Wizard shows it to be on the second step, Authentication, and the selected values are highlighted.

  15. Select Next.

  16. Select port2 for the Local Interface.

  17. Enter the local subnet range:

    • forti1: 172.16.0.0/16
    • forti2: 172.17.0.0/16

    If you use a different IP range, enter your IP range.

  18. Enter the appropriate remote subnets that represent the on-premises network to which you connect through the on-premises VPN device:

    • forti1: 172.16.0.0/16
    • forti2: 172.17.0.0/16

    If you use a different IP range, enter your IP range.

    Screenshot shows the VPN Creation Wizard on the third step, Policy & Routing, showing the selected and entered values.

  19. Select Create

  20. Select Network > Interfaces.

    Screenshto shows the interface list with two interfaces: port1, which is configured, and port2, which isn't. There are buttons to create, edit, and delete interfaces.

  21. Double-click port2.

  22. Choose LAN in the Role list and DHCP for the Addressing mode.

  23. Select OK.

Repeat the steps for the other NVA.

Bring up all phase 2 selectors

When you complete this procedure for both NVAs:

  1. On the forti2 FortiGate web console, select Monitor > IPsec Monitor.

    The monitor for VPN connection conn1 is listed. It is shown as being down, as is the corresponding Phase 2 Selector.

  2. Highlight conn1 and select Bring Up > All Phase 2 Selectors.

    Screenshot shows that monitor and Phase 2 Selector are both shown as up.

Test and validate connectivity

You can now route between each VNET through the FortiGate NVAs. To validate the connection, create an Azure Stack Hub VM in each VNET's InsideSubnet. You can create an Azure Stack Hub VM through the portal, Azure CLI, or PowerShell. When creating the VMs:

  • Place the Azure Stack Hub VMs on the InsideSubnet of each VNET.
  • Don't apply any NSGs to the VM upon creation. Remove the NSG that gets added by default if you create the VM from the portal.
  • Ensure that the VM firewall rules allow the communication you're going to use to test connectivity. For testing purposes, disable the firewall completely within the OS, if possible.

Next steps

Differences and considerations for Azure Stack Hub networking
Offer a network solution in Azure Stack Hub with Fortinet FortiGate

  • Last updated on