You need to make sure that this router is running DDWRT firmware which can be downloaded from http://www.buffalotech.com/support/downloads
From here you have to configure the firmware to allow the router to be an access point to your linksys. Keep in mind that this is not guaranteed to work.
After you flash the firmware to the DDWRT version you have to log into the router and go to setup
When you are in here you have to make sure that the WAN connection type is set to disabled. Then you have to assign the router a static ip address with an ip that is open on your network and is far above the start of your dhcp pool (just so any other devices do not try and use this ip address). Then you have to assign the default gateway which will be the ip address of your linksys. From here go ahead and press apply. You will then have to log into the new ip address and make sure that the dhcp server is disabled.
Once this is done you have to go to wireless settings. In here you have to make sure that the unit's wireless mode is set to WDS station. Then you have to make sure that the wireless network name SSID is the same SSID that your linksys is putting out. It IS case sensitive. Once that is set go ahead and press apply.
Once the page comes back go ahead and click on add under virtual interfaces. You can set this up as normal. This will the wireless information that your buffalo router will be putting out so that your devices can connect. This SSID HAS TO BE DIFFERENT then the main routers SSID. Once you are done with your settings press apply and save settings.
Now go to wireless security. Here make sure that your encryption settings and password are identical to the linksys. If they are not it will not connect. Once this is done you can go down to the virtual interfaces and set your wireless security on the buffalo router. This security information can be the same or different.
After that is all set up go to Services and then firewall. Make sure SPI firewall is disabled.
Restart both routers. This should complete the set up and your new buffalo should be getting an ip address from your Linksys and retransmit the wireless so your wireless devices can get online.
*****I no longer work for Buffalo and I am not an admin or mod but I'm still happy to help!******
-My products "LS-WVL, CS-WVL, WZR-HP-G450H, WZR-HP-G300NH x 2, WHR-HP-G54"
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