extend airport extreme network via ethernet to airport express (special case)

Question

Level 1

0 points

extend airport extreme network via ethernet to airport express (special case)

This question has been asked many times on the forum, and answered many times, but I have a special case and would like to know if it can be made to work.

As you can see, the issue is that the LAN port of the Extreme is not connected back to the switch, I've only connected the WAN port of the Extreme to the switch. Therefore the express doesn't get an IP over the CAT5e cable coming from the switch, and will only extend wirelessly. The reason I don't make that connection is because the switch/modem is in the basement, the Extreme is on the second floor, the express is on the far side of the first floor, and I don't want to run another cable through the house.

First question is, can the given topology be made to work?

If the answer is no, then would it work to put an additional switch on the second floor like the following?

Thanks!

airport extreme-OTHER, OS X Mavericks (10.9.5)

Posted on Sep 26, 2014 7:15 AM

Reply

Answer 1

Sep 26, 2014 8:52 AM in response to cmosmaster

First question is, can the given topology be made to work?

No, if your requirements are to extend using Ethernet.

then would it work to put an additional switch on the second floor like the following?

No, the modem must connect directly to the WAN port on the AirPort Extreme, assuming that you have a simple modem as pictured. Otherwise, the setup will work to extend using Ethernet.

Reply

Answer 2

cmosmaster Author

Level 1

0 points

Sep 26, 2014 9:33 AM in response to Bob Timmons

No, the modem must connect directly to the WAN port on the AirPort Extreme

I'm not sure I understand. What are you saying would not work? Right now I have topology 1, and the network is fine, except of course the Express is wirelessly extending, rather than using Ethernet.

Are you saying if I added the second switch the network would extend over ethernet to the Express but my uplink to the internet from my Extreme would break?

Reply

Answer 3

Sep 26, 2014 9:49 AM in response to cmosmaster

That is exactly what I am saying.

Remember, the modem has only one Internet IP address that it can deliver to a router. It is the router that assigns "local" IP addresses your other devices to "share" the Internet connection.

If you connect the Modem to the Switch, then it will be matter of chance as to which device......the AirPort Extreme or AirPort Express will get the valid IP address. The "other" AirPort will not be able to connect to the network.

Bottom line.....if you have a simple modem, as you have pictured, then it must connect directly to the WAN port on the "main" AirPort router. Something like this, for example:

Reply

Answer 4

cmosmaster Author

Level 1

0 points

Sep 26, 2014 9:56 AM in response to Bob Timmons

Thanks Bob, I see the error in my ways. Now I happen to have a wired-only router, so if I were to build something like:

modem <-> Wired Router <-> Switch? <-> Extreme

<-> Express

Could that somehow be made to work where the extreme and express are creating roaming network and are both just AP's?

Thanks again!

Reply

Answer 5

Sep 26, 2014 10:14 AM in response to cmosmaster

That will work. You can add as many switches as you want, as long as they are all "downstream" from the router.

Reply

Answer 6

May 23, 2015 4:42 PM in response to Bob Timmons

Sorry to necro an old thread, but I'm having an issue with a setup very similar to what's being described here. I've got my modem connected to my 4th Gen Time Capsule which connects to another GB switch and then out to two 2nd Gen Airport Express devices. According to the Airport Utility help file, the only way to do this is to "Make sure the device assigns a range of real IP addresses. Private IP addresses used by Network Address Translation (NAT) cannot be used for roaming." This isn't really possible since I get one IP address from my cable company (unless I'm missing something). Am I missing something (or with an upgrade to the newest models fix this)?

If I forgo the Ethernet connections and just extend the 802.11n WLAN wirelessly, I end up with a situation where the one Express connects through the other Express. As a result, wireless devices in the area that I'm trying to get coverage to can't connect. Is there a way to force each Express device to connect only to the Time Capsule?

Reply

Answer 7

May 23, 2015 8:25 PM in response to shortnuke

According to the Airport Utility help file, the only way to do this is to "Make sure the device assigns a range of real IP addresses. Private IP addresses used by Network Address Translation (NAT) cannot be used for roaming."

The proofreader must have had an off day. This information is not correct, and should be ignored.

In the illustration below....taken directly from an Apple support document about how to set up a roaming network.....the three devices that you see at the far right of setup are all receving Private IP addresses from the "main" router connected to the modem.

Reply