GRE Tunnel configuration examples

Introduction

Generic Routing Encapsulation (GRE) is a tunneling protocol that can encapsulate a wide variety of network layer protocols inside virtual point-to-point links over an Internet Protocol network.

This article provides an extensive configuration example with details on how to create a tunnel connection between two GRE Tunnel instances, both of which configured on RUTxxx routers.

Configuration overview and prerequisites

Before we begin, let's overview the configuration that we are attempting to achieve and the prerequisites that make it possible.

Prerequisites:

• Two RUTxxx routers of any type (excluding RUT850)
• Both routers must have a Public Static or Public Dynamic IP addresses
• At least one end device (PC, Laptop, Tablet, Smartphone) to configure the routers

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Configuration scheme:

As indicated by the figure above, the configuration we are trying to achieve here is very basic: it concerns two RUTxxx routers - RUT1 and RUT2. They are connected into a virtual network via a GRE Tunnel.

Router configuration

If you have familiarized yourself with the configuration scheme and have all of the devices in order, we can start configuring the routers using instructions provided in this section:

• Login to the router's WebUI and go to Services → VPN → GRE Tunnel. Enter a name for the new instance and click the "Add" button. Do this on both routers:

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• Click the "Edit" button located to the right of the newly created GRE Tunnel instance to enter the settings window.