Enabling OpenVPN Server on Linksys WRT1900ACS with Stock Firmware

Introduction

This article provides a step-by-step guide on how to enable and configure an OpenVPN server on a Linksys WRT1900ACS router running stock firmware. OpenVPN is an open-source software application that implements virtual private networks (VPNs) with a focus on security and flexibility.

Prerequisites

Before proceeding with the setup, ensure the following:

• Linksys WRT1900ACS router with stock firmware version 1.0.3.187766 or later
• Basic understanding of router configuration and networking concepts

Enabling OpenVPN

To enable OpenVPN on the Linksys WRT1900ACS, follow these steps:

1. Access the router's web interface by entering its IP address (usually 192.168.1.1) in a web browser.
2. Log in using the administrator credentials (default: admin/admin).
3. Navigate to the "Administration" tab and select "Services."
4. Locate the "OpenVPN" section and check the box next to "Enable OpenVPN."
5. Click "Save Settings & Restart" at the bottom of the page.

Configuring OpenVPN

Now that OpenVPN is enabled, we need to configure it:

1. Navigate to the "Services" tab and select "OpenVPN."
2. Under "Server 1," enter the following details:

 Prot 1194
 Dev tun
 Server 192.168.1.1 192.168.1.100 192.168.1.0 255.255.255.0
 TLS-Auth /tmp/openvpn-auth.key 0 # This file is generated during the setup
 Cipher AES-256-CBC
 Auth SHA256
 Keysize 256
 Tunnel-Protocol tcp,udp
 Compression lz4

Replace "192.168.1.100" with the static IP address assigned to the router's OpenVPN interface.

2. Under "Server 1," go to the "TLS Certificates" tab and generate new certificates:

 Generate Self-Signed Certificate
 Common Name: router
 Organization: Your Organization
 Organizational Unit: Your Organization Unit
 City: Your City
 State: Your State
 Country: Your Country
 Email: [email protected]
 Passphrase: your-password
 

Save the generated certificate files and remember the passphrase.

3. Under "Server 1," go to the "Client Export" tab and export the client configuration file:

 Export All Clients
 Export Client File: openvpn-client.ovpn
 

Save the exported file to a secure location.

Setting Up the Client

Install OpenVPN client software on your device and import the exported client configuration file.

Verifying Connection

Connect to the OpenVPN server using the client software and verify the connection by:

• Checking the client's IP address assignment in the router's OpenVPN client list.
• Pinging the OpenVPN server from the client.

Congratulations! You have successfully enabled and configured an OpenVPN server on your Linksys WRT1900ACS router running stock firmware.