I have configured a Linksys WRT600N to connect using PPTP to my company’s VPN server in the past as noted in this previous article. I have since swapped out the Linksys WRT600N with a Linksys WRT54GS because I wanted to replace the antennas with larger antennas to work on getting better wireless coverage in my workshop in the basement and with the primary wireless router being located on the second floor of my house I needed to do numerous things to squeeze as much signal as possible. I also noticed numerous other issues with the WRT600N including the router locking up on a regular basis as well as dropping connections.
Anyhow I wanted to add a new article explaining the process of connecting a Linksys WRT54GS to the office VPN server in case others also needed to do so and couldn’t find my previous article based on the WRT600N. The VPN Server at the office is a Linksys RV016 though these instructions should be very similar for most Point-To-Point Tunneling Protocol VPN connections. The below directions should work exactly the same on any wireless router running dd-wrt since the firmware code base is the same for each router. Also note that the Linksys WRT54GS is the same as the Linksys WRT54G except for the addition of “SpeedBoost” software, typically more RAM, and typically more flash memory. Follow the directions below to configure your Linksys WRT54G wireless router running dd-wrt, an open source Linux based firmware, as a PPTP client to connect to a remote VPN server.
DD-WRT PPTP Client Configuration Steps:
- DD-WRT Administration: First connect to the administration page of your router by visiting the internal IP address of the router such as https://192.168.1.1 . Type in your login information in the authentication box that will pop up as shown below.
Once logged in you will be at the DD-WRT System Information window as shown below.
- PPTP Configuration: To get to the PPTP Configuration page first click on the Services tab in the top navigation window. Next click on the PPTP tab in the Services sub navigation menu.
- Configure PPTP Client: Now we will fill in the PPTP Client configuration options as shown below.
The PPTP Client options to connect DD-WRT to a Linksys RV016 are detailed below.
PPTP Client Options: Enabled
Server IP or DNS Name: 126.96.36.199
Remote Subnet: 192.168.19.0
Remote Subnet Mask: 255.255.255.0
MPPE Encryption: mppe required,no40,no56,stateless
User Name: exampleuser
The first configuration option “PPTP Client Options” is set to enabled to make sure it is operational. Next the Server IP or DNS Name is the address of the remote VPN Server which in my case is the Linksys RV016 at our office. The Remote Subnet and Subnet Mask details the IP address information of the local network on the PPTP VPN Server. One of the less obvious configuration options is the MPPE Encryption which in this configuration example is required. Please note that it is not always required and some of the options may need to be modified in your scenario such as the connection being stateful or stateless. If these options don’t work for you either ask a question in the comment section or search the Internet for MPPE Encryption. The next option is NAT or Network Address Translation which is enabled in the example. Last but not least is the user name and password required to authenticate your PPTP connection.
- Save & Apply PPTP Client Configuration:Now click the Save button located at the bottom of the DD-WRT PPTP configuration page. Just because the configuration page has been saved does not mean the PPTP Client configuration is active. To make the PPTP Client connection become active you must click the Apply button which will reboot your router which in this case is the Linksys WRT54GS. Make sure you click the Save button first as just clicking the Apply button risks losing the new configuration.
- Verify PPTP Client Connection:There are numerous ways to verify that the PPTP Client connection is established and functioning properly. Please note that the connection may take a couple minutes to establish and may need to be restarted at later times if the connection has become stale by a loss of Internet connectivity or many other reasons. You can actually watch the connection establish on your router by opening an SSH connection and typing “ps” from the CLI to watch the process list. After the connection is established you will see a line similar to the below in the output of “ps”.
- 4182 root 1320 S pptp: call manager for 188.8.131.52
This process shows that a connection is established to the PPTP server at 184.108.40.206. So once this PPTP connection is established you should now be able to communicate with devices on the remote network which in this case is the 192.168.19.0/24 network. So from any computer on my local network I should now be able to ping remote devices that are located on the local network of the RV016. If there was a server at 192.168.19.133 I should now be able to type “ping 192.168.19.133” from my laptop and receive a echo response from the ICMP request. If this is successful we know that the PPTP VPN connection is established and operational!
The above configuration example can be tweaked to work with pretty much any PPTP VPN server located on the remote end of the VPN connection. Configuring your office VPN connection at the router is much more convenient than having to start and stop the connection from your PC every time you want to establish a VPN connection to your office.