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DHCP option 82 and Pix 501

I'm trying to get my Pix 501 to get a address from my service provider. I am connecting to the internet via cable modem. The Pix fails to get an IP address. I did a debug and it seems the service provider is sending DHCP option 82. What do I have to configure to get the PIX to pickup an address ?

Cisco Employee

Re: DHCP option 82 and Pix 501

The PIX should just ignore the option. what does "debug dhcpd" show you. If you plug a PC intothe cable modem, does it get an address OK? Make sure that after you then remove the PC and plug the PIX back in, that you reset the cable modem, as a lot of the remember the last MAC address and won't allow anything new to connect until they're reset.

Failing that, there's a known issue (CSCdw17097) with DHCP and the PIX, in that it won't be able to gt an address if the broadcast bit in the DHCP packet is set. This has been fixed for quite a while in all major releases, so upgrade to 6.2(2) if you're at something earlier and then at least you know you're not hitting that.

Usually the problem here is simply that the cable modem needs resetting though (seen it 100's of times)

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