Configure a Pre-PAN-OS 10.0 Firewall for a Local DHCP Server
When a firewall is running a PAN-OS release earlier than
PAN-OS 10.0 and there’s a local DHCP server, configure the firewall
as a DHCP relay agent.
When the firewall is not receiving unicast
DHCP packets—either as a DHCP server or relay agent—you must arrange
for it to generate or receive them. Instructions for doing this
to provide DHCP traffic visibility in PAN-OS 8.1, PAN-OS 9.0, and
PAN-OS 9.1 are provided in this section.
In the example below, there is a DHCP server on the local network
segment. The firewall receives the DHCPDISCOVER messages that DHCP
clients broadcast, but it is not configured as a DHCP server.
Solution 1: Move the DHCP Server to a Different Zone
This solution involves moving the DHCP server to a different
zone on the firewall and configuring a DHCP relay agent on the firewall
interface that connects to the clients. This forces the generation
of unicast DHCP traffic, which the firewall can then use to generate
Enhanced Application logs (EALs).
Solution 2: Place the DHCP Server behind a Virtual Wire
Placing the DHCP server behind a Virtual Wire interface enables
the firewall to generate EALs for all packets in the exchange. After
proper configuration and physical network changes, the network looks
similar to the illustration below: