Cannot setup Airport Express to work other than in bridge mode

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Cannot setup Airport Express to work other than in bridge mode

I set up an Airport Express in my apartment, which is serviced by a T-1 line, after providing the ISP with the MAC address of the device. During set up with Airport Utility, the instructions ask that I turn off the modem; because that is not possible I skip that step and complete set up. By default this seems to put the device into Bridge mode. This allows me to connect my MacBook, but I am unable to connect any other devices (iPhone, roku, etc.) to the Wifi network. On the network tab, I tried to change the network to DHCP, but I keep getting an error message that there is an invalid value and that I need to manually configure my WAN IP address. If I try to change the DHCP range of addresses on the Network tab, it only allows me to change the final digits (but anything I tried changing it to resulted in another "Invalid value" error message.

If I click on Review Settings in the error message box, it takes me to the Internet set up tab which would only allow me to change the DNS servers. No matter what public DNS servers I try to use, I get the same "Invalid value" message above. I don't see anyway to "manually configure your WAN IP address."

Any suggestions?

Posted on Apr 16, 2015 5:56 PM

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Answer 1

Tesserax

Level 10

158,616 points

Apr 16, 2015 7:28 PM in response to icaforpj

The "DHCP Only" mode was designed to distribute multiple Public IP addresses from your ISP to devices on your local network. I don't believe this is what you are looking for.

What is the make & model of the modem that you have your AirPort Express connected to by Ethernet? Which exact model of Express do you have?

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Answer 2

icaforpj Author

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Apr 16, 2015 7:39 PM in response to Tesserax

There is no modem...a cat-5 cable comes into the apartment delivering the T-1 service. It gets plugged into the WAN port. Airport Express Version 7.6.5.

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Answer 3

Tesserax

Level 10

158,616 points

Apr 17, 2015 9:07 AM in response to icaforpj

Sorry, then the AirPort base stations may not work in your situation as they require a direct Ethernet connection to a modem.

Placing the Express into bridge mode would require that the upstream device provide both NAT & DHCP services in order to support multiple clients on your local network with Internet access.

What happens when you configure the Express to have both of these services enabled?

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Answer 4

icaforpj Author

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Apr 16, 2015 8:07 PM in response to Tesserax

Error results..."Double NAT". "This AirPort base station has a private IP address on its Ethernet WAN port. It is connected to a device or network that is using Network Address Translation (NAT) to provide private IP addresses. Change your AirPort base station from using DHCP and NAT to bridge mode."

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Answer 5

Bob Timmons

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186,926 points

Apr 17, 2015 7:35 AM in response to icaforpj

You already know that Bridge Mode will only allow one device to connect on your network and that the DHCP Only setting is not appropriate for the type of service that you have, so your only option is to run the Express in a Router Mode of DHCP and NAT to allow multiple devices to connect to your network.

Apple does provide you with an easy one click way to "ignore" the Double NAT status message of a blinking amber light so that the Express will display a green light......so this is not really a serious "error" at all, simply a different and slightly more complicated option for connecting a network device.

I use a Double NAT setup all the time when I'm traveling and want to connect the Express to the Ethernet port in a hotel room. Things work fine, including the ability to connect multiple devices to my own private network that the Express provides.

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Answer 6

icaforpj Author

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Apr 17, 2015 7:52 AM in response to Bob Timmons

Thanks for that. I actually clicked on the "ignore" option last night and saw the green light, but my cell phone still wouldn't connect. I probably should have restarted the router at that point, but it was late and I gave up...I will try again tonight following your suggestion.

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Answer 7

Bob Timmons

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186,926 points

Apr 17, 2015 9:07 AM in response to icaforpj

It would be a good idea to start all over again from a factory default condition on the Express.....if you have not already done so.

With the Express powered on, hold in the reset button on the back of the Express for 8-10 seconds, release and allow a full minute for the Express to restart to a slow, blinking amber light status.

Then, set it up again.

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Answer 8

minnaqua

Level 1

9 points

Jul 18, 2015 12:18 PM in response to icaforpj

Do you know how to go in and change AirPort base station from using DHCP and NAT to bridge mode? Thanks so much!

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Answer 9

Tesserax

Level 10

158,616 points

Jul 19, 2015 3:54 PM in response to minnaqua

You would do so using the AirPort Utility as follows:

Run the AirPort Utility. Note: For the following instructions I am assuming that you are running the AirPort Utility on an iOS device.
Select your AirPort base station, and then, select Edit.
Select Advanced.
Select the DHCP and NAT option.
Set Router Mode to: Off (Bridge Mode)
Select Done and allow the base station to restart.

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