DHCP RELAY over L2TPv3
Introduction
A DHCP relay agent allows the DHCP clients to obtain IP addresses from a DHCP server that is not configured on the same LAN.
This article provides a configuration example with details on how to set-up a DHCP relay over a L2TPv3 VPN.
Prerequisites
You will need:
- Two RUT or RUTX devices (one as Server and other as Client)
- A PC acting as a Host for testing
- Both routers must have a Public Static or Public Dynamic IP addresses
Configuration Scheme
I will paste a Topology Image here
DHCP Server Settings
DHCP Pool
Enter the router's WebUI, go to Network > Interfaces > Ethernet LAN and click the 'Edit' button on the right side of the interface to set the LAN network address.
Under DHCP SERVER set parameters for the DHCP pool.
Set up Mobile WAN as Main WAN
Enter to the router’s WebUI, go to Network > Interfaces press mouse click on the Mobile Wan interface, then drag it to the 1st position and then press Save & Apply.
Create L2TPv3 instance
Go to router’s WebUI, under Service > VPN > L2TP > L2TPv3 and create new L2TPV3 instance.
LOCAL SETTING
Local address: 84.15.155.201
Tunnel ID: 100
Session ID: 100
Cookie: 12ABCDEF
PEER SETTING
Peer address: 84.15.249.182
Peer Tunnel ID: 10
Peer Session ID: 10
Peer Cookie: 12ABCDEF
INSTANCE SETTING
Bridge to: LAN
MTU: 1500
Encapsulation: IP
Layer 2 specific header type: Linux Default