05-23-2007, 11:52 PM
cable wire to Comcast wireless router
ethernet cable from Comast router --> Airport Extreme and Airport Expresses.
The Airport expresses have been formatted to connect to the Airport Extreme, but I've understood that Comcast has a maximum allowable "units" at 5.[\QUOTE]
I see a problem possibly. Typically the Comcast device is a "Glorified Ethernet Modem", with input of COAX, and output of Ethernet. Does you Cable Modem have more than one Ethernet port?
Even so, NAT should fix all this... Say even your Comcast Modem has more than one port, you can assign the AP Extreme to use the gateway or static IP of the modem, or set the AP Extreme automatically with DHCP. Might have to try to restart the Modem then AP Extreme to ensure the DHCP is being sent to the AP Extreme. If this does not prove to work manually input the IP of the Comcast modem... Mine was 192.168.1.100, but that was a long time ago - Motorolla Surfboard 6200. Hopefully at this point your AP Extreme should be talking to Modem. Then have the AP Express to use the gateway of the AP Extreme (192.168.1.1). This should almost be automatic, but might be required to be plugged in.
Unless I'm missing something, or lost the concept of what your trying to do this fore mentioned would be my starting point.