How to use DHCP Relay over an IPsec tunnel?
Vigor router can act as a DHCP Relay Agent and let hosts get an IP address from another DHCP server, which can be in another LAN subnet, or even in the remote network. It will be easier for administrator to use only one DHCP server for the entire network. DHCP Relay over VPN makes the network not be limited by location, and allows network administrator in a global company to manage all the branch offices with just one DHCP server.
The following example shows how to set up Vigor Router to relay DHCP requests to the DHCP server on 192.168.0.100.
1. Establish a VPN tunnel between local and remote network. The process of creating a VPN please refer to Vigor Router to Vigor Router - IPSec Tunnel (Main mode), but please note that, to use the DHCP Relay, it's necessary to enable Multicast via VPN in the VPN profiles.
2. After VPN established, enable DHCP Relay Agent on both routers. Go to LAN >> General Setup,
- Disable DHCP Server and Enable Relay Agent
- Enter DHCP Server IP Address as the IP address of the DHCP server
- Click OK to apply.
3. Now, the host can get an IP address from DHCP server through VPN tunnel.