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Cisco PIX 525 is not allowing DHCP address to be applied to router

Cisco PIX 525 is not allowing DHCP address to be applied to router

Cisco PIX 525 is not allowing DHCP address to be applied to router


I currently have a Cisco PIX 525 firewall running version 7.0(1) and ASDM 5.0(4). It is running in transparent mode, and it is connected between my Time Warner Cable [TWC] modema and F0/0 on my Cisco 3660 router. When I reload the router, the router cannot obtain the DHCP IP address from TWC. I have to disconnect the LAN cable from the PIX outside interface and connect it directly to the F0/0 on the router, allow the DHCP address to be obtained, and then reconnect the TWC modem back to the outside interface. About every 24 hours, I ahve to continue to the the same process when the router's DHCP lease ends. I know there are other ways around it (ie. configuring the PIX in router mode, getting rid of the PIX and using the firewall ability in the router's IOS), but this is the hardware configuration I would like to use. I am unfamiliar with setting up a PIX / Firewall, and I would like to use this as one of my many learning experiences. What IOS command sequence, or ASDM configuration screen(s) settings, would I use to allow DHCP IP and DNS requests and addresses to pass through to the inside interface and ultimately the router?


RE: Cisco PIX 525 is not allowing DHCP address to be applied to router

First off this is the forum for routers. There is a separate one for PIX http://www.tek-tips.com/threadminder.cfm?pid=35

What you need the feature called DHCP relay. The feature is not available in transparent mode.

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