DHCP relay
While using a remote DHCP server (on another network segment), the DHCP relay service will need to be configured. This is required because the DHCP protocol works using broadcasting requisitions on the network, and as we already know, the broadcast domain is limited to the same network in which the hosts reside. OPNsense supports both DHCPv4 and DHCPv6 relaying.
Important Note
The DHCP relay service can only be used on an interface that has the DHCP server disabled.
To start configuring the DHCP relay service, go to Services | DHCPv4 | Relay or Services | DHCPv6 | Relay for the IPv6 protocol.
For both IP protocol versions, v4 and v6, the configuration options are the same. Here are descriptions of each one:
- Enable: Check this option to enable the DHCP relay service.
- Interface(s): Select each interface to be configured as the relaying service.
- Append circuit ID: Check this option to add a circuit ID—which means the OPNsense interface number...