topic Configuring PIX to allow DHCPRelay Agent in Network Security

Configuring PIX to allow DHCPRelay Agent

raun.williams — Mon, 11 Mar 2019 11:31:43 GMT

I'm attempting to pass IP's from my pix501 (which is the dhcp server) to clients on the wireless lan controller. The controller acts a dhcp relay agent and I get this in my pix debug:

DHCPD: DHCPDISCOVER received from client 0100.18de.19ab.b9 through relay 192.168

.83.253.

, packet discarded

What can I do to force the pix to allow this through and reply with an IP for the client?

Thanks,

Raun

Re: Configuring PIX to allow DHCPRelay Agent

irisrios — Wed, 21 Nov 2007 20:03:58 GMT

On the controller you would normally associate an interface to a WLAN. While creating an interface that corresponds to the WLAN you have an option to specify DHCP server . Configure PIX as a DHCP server and see if this works.

Configuring PIX to allow DHCPRelay Agent

shensimpson — Thu, 06 Feb 2014 15:18:11 GMT

Hi,

I am having the same issue, just wondering if anyone has found a solution. I am trying to configure an Alcatel Wireless controller to use a PIX firewall. Wireless clients are not able to obtain an ip address via DHCP. The PIX reports:

DHCPD: DHCPDISCOVER received from client 0100.1302.5e8f.50 through relay 192.168.10.2

, packet discarded

Notice that the client Mac address is too long "01" is being added to the beginning. I have verifified that the Alcatel controller works when connected to a "Linksys" broadband router.

I would greatly appreciate any help you can offer.

Shen

Configuring PIX to allow DHCPRelay Agent

Jouni Forss — Thu, 06 Feb 2014 22:28:01 GMT

Hi,

To my understanding no Cisco firewall model will support acting as a DHCP server for hosts which DHCP messages are relayed by another device in between the client and the firewall. They would only be able to act as a DHCP server to a directly connected network or relay DHCP messages from a directly connected hosts to a server behind another interface of the same firewall.

- Jouni

Configuring PIX to allow DHCPRelay Agent

shensimpson — Fri, 07 Feb 2014 15:12:33 GMT

Yeah that's the conclusion I came to as well. From the Cisco PIX command reference:

"The PIX Firewall DHCP server daemon does not support clients that are not directly connected to a

firewall interface"

Thanks for your help!