This document is a walk-through for setting up a virtual MX appliance (vMX) in the Azure Marketplace. After completing the steps outlined in this document, you will have a virtual MX appliance running in the Azure Cloud that serves as an Auto VPN termination point for your physical MX devices.
Note: Some Azure regions such as South Africa West require Azure support to enable the ability to deploy the Standard F4s_v2 VM instance type required by the Meraki vMX. The process for requesting access to these regions is documented by Microsoft in the Azure region access request process. Meraki vMX is only supported on instance types mentioned in this KB, other instance types are not supported.
Before deploying a vMX, it is important to understand several key concepts.
All MXs can be configured in either NAT or VPN concentrator mode. There are important considerations for both modes. If needed, refer to the article on concentrator modes for more detailed information.
In this mode, the MX is configured with a single Ethernet connection to the upstream network. All traffic will be sent and received on this interface. This is the only supported configuration for MX appliances serving as VPN termination points into Azure Cloud.
NAT Mode Concentrator
In this mode, any traffic coming over auto-VPN or client VPN to the vMX will be NATed to the vMX's IP as it egresses the vMX. Other capabilities of the NAT mode including DHCP, HA or multiple ports (LAN and WAN) are not supported. In this mode the vMX is still a one-armed appliance with one network interface.
Change in default behaviour
All new vMXens deployed post October, 31, 2022 will be deployed in Routed/NAT Mode Concentrator by default, existing vMX deployments will not be effected. If you wish to use the vMX in passthrough mode, please change the deployment settings to Passthrough or VPN Concentrator mode from the Security& SD-WAN > Configure > Addressing & VLANs page.
There are several options available for the structure of the VPN deployment.
In this configuration, branches will only send traffic across the VPN if it is destined for a specific subnet that is being advertised by another MX in the same dashboard organization. The remaining traffic will be checked against other available routes, such as static LAN and third-party VPN routes, and if not matched will be NATed and sent out the branch MX unencrypted.
In full-tunnel mode, all traffic that the branch or remote office does not have another route to is sent to a VPN hub.
Azure Cloud Terminology
This document will make reference to several key Azure-specific terms and concepts.
Azure Virtual Network
A virtual network is where a block of associated IP addresses, DNS settings, security policies, and route tables can be configured and managed.
Azure Resource Manager (ARM) and Azure Classic
Azure has different types of virtual network environments, which represent two different methods of deploying and managing Azure virtual environments. The vMX uses managed applications, which is a Microsoft platform, and is not compatible with Azure 'classic' deployments.
A resource group is a container within Microsoft Azure's infrastructure where resources such as virtual machines are stored.
Managed applications within Azure serve as the network used to manage and support the Cisco Meraki vMX.
During the setup of your vMX instance, or over the course of working within Azure, you may encounter additional terminology which is not defined in this document. To find out more about these terms, and for additional details on the terms listed above, please see the Microsoft Azure glossary.
Meraki Dashboard Configuration
Begin by creating a new Security Appliance network in your organization. This guide will walk you through creating a new network in the Meraki dashboard.
1. Adding license(s) to the Meraki dashboard
The Meraki Dashboard will require a vMX license to be added before you are able to continue. If you do not have access to a vMX license, please reach out to your Meraki reseller or sales rep.
Create a "Security appliance" network type:
Once you have created the "Security appliance" network and added the appropriate license, you will be able to deploy a new vMX to your network by clicking on the 'Add vMX' button:
Before generating the token, please verify the firmware is running MX 15.37+, otherwise the upgrade will not occur.
2. Generate the authentication token
After you add the new vMX to your network, navigate to Security Appliance > Appliance status and select “Generate authentication token” to generate the token for the Azure "Meraki Authentication Token" data field.
3. Copy the newly generated token and save it.
The newly generated token will be used in the Basics -> Instance details section when creating a new Azure-managed application.
The authentication token must be entered into the Azure instance within one hour of generating it, otherwise a new token must be generated.
This section walks you through configuring the necessary requirements within Azure and adding a vMX instance to your Azure virtual network. For more details on setting up an Azure virtual network and other components, please refer to Microsoft Azure Documentation.
Before You Begin
You must have the following before you begin:
An Azure virtual network (vNET, also known as a VPC) where you will deploy the vMX. This vNET and its corresponding resource group can be the same one as the resources you plan to access across the Meraki VPN or a different one. Refer to this Azure document for creating these resources.
You MUST have an "SD-WAN" subnet inside the vNET where the vMX will be deployed which is separate from the subnet(s) where the resources you plan to access through the VPN are hosted. Ex. If your apps and resources are located in the "production" subnet, you will deploy a second subnet in the same vNET called "SD-WAN" in which the vMX will be deployed. DO NOT deploy the vMX inside the production subnet alongside the other resources as this can result in a routing loop and packet loss within the Azure environment.
A NOTE FROM AZURE:
Deploy a virtual appliance into a different subnet than the resources that route through the virtual appliance are deployed in. Deploying the virtual appliance to the same subnet, then applying a route table to the subnet that routes traffic through the virtual appliance, can result in routing loops, where traffic never leaves the subnet.
This section walks you through configuring the necessary requirements within Microsoft Azure, and adding a vMX instance to your resource group. For more details on setting up a resource group and other components, please refer to Azure's documentation.
Accessing the Offer
Access to the vMX offer. A screenshot of the Marketplace list of Cisco Meraki vMX in Azure is included below:
The same vMX offer is also available via Cloud Solution Providers (CSP) program on Azure.
From the Marketplace listing, click on "Create."
After creating, you will be prompted to configure basic settings for the managed app.
Subscription: Choose the subscription that you want to be billed for from the drop-down menu
Resource group: Create a new resource group with any name or select an existing resource group
VM name: Choose a name for your Cisco Meraki vMX VM; it can be any name
Meraki authentication token: Paste the token previously generated on the Meraki dashboard
Region: Select the region where the vMX will be deployed
Zone: Select the appropriate Availability Zone (AZ) for the region selected above
Not all regions on Azure support Availability Zones (AZ). Select “NONE” for zones that don’t support AZs. If a zone is selected for a region that does not support AZs, the deployment will fail.
Managed Application Details
Application name: Choose a name for your Cisco vMX managed application
Managed resource group: Name for the managed resource group, which will hold all the resources that are required by the vMX managed application
After completing the basic settings configuration, go to the next step, “Deployment Details.”
Configure virtual networks
Virtual network: Choose an existing virtual network from the list; minimum allowed prefix size for the virtual network is /24 and max is /8
Subnet: Choose the SD-WAN subnet mentioned above in which the vMX will be deployed; if needed, refer to the article for more information about subnets in Azure. The subnet chosen here MUST be different from the subnet where resources you plan to access and route through the vMX are deployed.
VM size: Choose the VM size based on the vMX SKU you want to deploy. For best performance, the new instance type of "Standard F4s_v2" should be used to deploy the vMX-S and vMX-M SKUs.
Next, review the deployment details and licensing information and hit "Create."
After you click on "Create," the deployment will begin.
It may be several minutes before the deployment completes and the instance launches.
Once the vMX is online, a route table needs to be created including the Auto VPN subnets so that the Azure resources know how to access the Meraki subnets over Auto VPN.
Additional Azure Route Table Configuration
To create a route table, click on "New" and then "Route Table."
Next, define the “Basics” for the new route table resource.
Route Table Basics
Subscription: Choose the subscription that you want to be billed for from the drop-down menu
Resource group: Choose an existing or a new resource group where your instances are present or will be deployed
Region: Select the region where the route table will be deployed
Name: Name for the route table instance; can be anything
Propagate gateway routes: Default is "Yes;" select "no" to prevent the propagation of on-premises routes to the network interfaces in associated subnets
Once the Route Table has been created, add the VPN routes pointing to the vMX as the next hop, including the client VPN subnet where applicable:
Please ignore the IP forwarding warning, it has already been enabled in the managed application template by default.
Finally, associate the Route Table with the subnet where the resources are deployed (NOT the SD-WAN subnet where the vMX is deployed). Click on "Subnets" and then "Associate. Choose the virtual network and then choose the production subnet(s) where your applications are deployed and click "OK."
Do not associate the vMX SD-WAN Subnet to a route table as this is known to cause packet loss.
Once the subnet has been associated, enable site-to-site VPN on dashboard.
On the site-to-site VPN page, add each subnet in your resource group that should be accessible to remote Auto VPN peers to the list of "Local Network(s)." For more information on configuring Auto VPN, please refer to the site-to-site VPN settings documentation.
The most common problem when deploying a vMX is getting it provisioned and online in the Meraki dashboard in the first place.
Unable to reach Meraki Dashboard
If the vMX is unable to reach the dashboard on TCP port 7734, please refer to this document on the correct ports/IPs that need to be opened for Meraki dashboard communication.
No "Add vMX" Button
When navigating to Security & SD-WAN > Appliance Status, if there is no "Add vMX" button, please ensure the following two conditions are met:
- You have available vMX licenses in your license pool.
- You have created a "Security appliance" network type.
A few common fixes for (re)deployment failures could be:
- updating the VNET DNS settings
- removing any special characters in the name of the vMX
Packet loss is seen when accessing resources through the vMX
- Resources are not deployed in the same subnet as the vMX. Resources must be deployed in different subnets, with a route table applied to resource subnets allowing routing back to spoke sites. vMXen also support eBGP for route distribution with Azure Route Servers.
- The vMX SD-WAN subnet is not associated to a VNET Route Table. The vMX subnet will not require a route table to operate correctly, and associating a route table is known to cause general packet loss.
For more information from Azure: https://docs.microsoft.com/en-us/azure/virtual-network/virtual-networks-udr-overview#user-defined
This may also present as low SMB/CIFS throughput, as these protocols are extremely sensitive to loss.
Please note that Meraki Support does not troubleshoot Azure Cloud-specific firewall rules and deployments.