User guide

User Guide 75
Network Settings
About DHCP relay agents
One way to get IP addresses for the computers on the trusted or optional networks is to use a DHCP server on
a different network.
The Firebox can send a DHCP request from a DHCP client to a DHCP server at a different location through a
VPN tunnel. It gives the reply to computers on the trusted or optional network. This option lets computers in
more than one office use the same network address range. In this procedure, the Firebox is a DHCP relay agent.
You must set up a VPN tunnel between the Edge and the DHCP server for this feature to operate correctly.
Make the Firebox a DHCP relay agent for the trusted interface
To configure the Firebox X Edge as a DHCP Relay Agent for the trusted interface:
1. Use your browser to connect to the System Status page. From the navigation bar, select
Network > Trusted.
The Trusted Network Configuration page appears.
2. Select the Enable DHCP Relay check box.
3. Type the IP address of the DHCP server in the adjacent text box.
4. Click Submit. You must restart the Firebox X Edge for new configuration to start.
If the Firebox X Edge cannot connect to the DHCP server in 30 seconds, it uses its own DHCP server
to give IP addresses to computers on the trusted network. You must enable the DHCP Server on the
trusted network for the DHCP relay function to operate.