Connect AEBS-based LAN to existing WIFI using Airport Express

[wataguy]

I just moved into an apartment building with shared WiFi, and I have my own little WiFi LAN I use for development, comprising a laptop and server (for local use only). I was hoping to use an Airport Express to connect to the building WiFi in bridge mode, then plug that into the AEBS's WAN port, and run DHCP and NAT on the AEBS, thus protecting my local devices a bit from the depredations of others in the building — I live in Phnom Penh, so the problem's a bit more severe here than most places.

But I can't get it to work, and I've confused myself enough that I'm no longer sure what I've tried. Anyone want to a) LMK if this is a viable setup, and if so, b) the right way to set it up?

 

[Bruno09]

Hi,

does your Express have "n" wifi ?

The previous model (wifi b/g) can not be used to create a wireless bridge, since its Ethernet port is disabled in client mode.

"While in client mode, AirPort Express with 802.11n will be able to use the Ethernet port to pass Wi-Fi traffic to a device connected to the Ethernet port. However, the original AirPort Express 802.11g doesn't support this feature and will disable the Ethernet port"

http://support.apple.com/kb/HT1731?viewlocale=en_US&locale=en_US

 

[wataguy]

Yes, it's the 802.11n model and the AEBS is the 5th gen one (the last one before the current towers).

 

[Altemose]

Yes, it's the 802.11n model and the AEBS is the 5th gen one (the last one before the current towers).

It will work then but you may be running in a Double NAT configuration which may cause some applications to not behave properly.

 

[wataguy]

Huh. Weird. I tried setting it up a few times, and it kept failing as soon as I added the second computer. But the building has another WiFi network, and when I set up the Express to connect to that all was good.

So, something odd with the first WiFi I was using. Wish I knew what.

Anyway, thanks for listening.