---
title: "Azure"
description: "Reference for running Calico Open Source on Microsoft Azure covering supported networking modes, user-defined routes, and Azure platform notes."
product: "Calico Open Source"
version: "3.32 (latest)"
section: "Reference"
canonical_url: "https://docs.tigera.io/calico/latest/reference/public-cloud/azure"
---

# Azure

## About Calico on Azure

You can use Calico policy with one of the following networking options.

- **Azure user-defined routes**: This option provides networking without overlays. Disable Calico networking by setting `CALICO_NETWORKING_BACKEND` to `none` in `calico/node`. (Also called "policy-only mode".) Refer to [Configuring calico/node](https://docs.tigera.io/calico/latest/reference/configure-calico-node.md) and [Azure user-defined routes](#azure-user-defined-routes) for more information.

- **Calico VXLAN**: Install Calico using VXLAN encapsulation for pod traffic.

- **flannel** (Kubernetes only): Refer to [Installing Calico for policy and flannel for networking](https://docs.tigera.io/calico/latest/getting-started/kubernetes/flannel.md) for specific instructions and a manifest. This option does use overlays.

- **Azure CNI IPAM plug-in**: Configure Calico to use the [Azure CNI plug-in](https://github.com/Azure/azure-container-networking/blob/master/docs/cni.md) instead of the Calico CNI plug-in.

## Azure user-defined routes

To configure Azure user-defined routes (UDR):

- Create an [Azure route table](https://docs.microsoft.com/en-us/azure/virtual-network/create-user-defined-route-portal) and associate it with the VMs subnet.

- Enable [IP forwarding enabled](https://docs.microsoft.com/en-us/azure/virtual-network/virtual-network-network-interface#enable-or-disable-ip-forwarding) in your VM network interfaces.

On Kubernetes, also complete the following.

- Ensure that the selected pod's subnet is a part of your Azure virtual network IP range.

- Include the name of your routing table in the configuration file of your Kubernetes Azure cloud provider.

## Does Azure support Calico networking?

Calico in VXLAN mode is supported on Azure. However, IPIP packets are blocked by the Azure network fabric.