Re: Wireless Internet Connection drops when LAN Adapter Enabled

Shakka <Shakka.2t95co@no-mx.wirelessforums.org> hath wroth:

>_The_Setup_
>I have a Dell Optiplex 745 (new) and it came with a Broadcom NetXtreme
>57xx Gigabit NIC built in. I also have a Netopia 2247NWG-VGx wireless
>access point which I was using successfully with two other older PC's.
>I purchased a Realtek RTL8187 Wireless 802.11g USB wireless adapter for
>the Optiplex and have a very good signal to the wireless network. I'm
>running Win XP Pro SP2 on the Optiplex. All NIC drivers and Wireless
>drivers are the latest. The PC is connected via a network hub to a Win
>2003 SBS network.
>
>_The_Problem_
>I can connect wirelessly to the Netopia box using 192.168.1.254 all of
>the time so I know the USB adapter is OK. I can also connect to the
>Internet over wireless connection. If however, I enable the LAN Adapter
>within Windows, the Internet connection drops. I know this because I am
>running a Ping /t which will stay connected all day long if the LAN
>adapter is disabled, but drops the second the LAN adapter is enabled
>with a "Request Timed Out". The Instant I disable the LAN adapter, the
>Ping starts working again. BTW, when the LAN adapter is enabled, I can
>still connect to the Netopia box wirelessly. It's strictly the Internet
>connection thats dodgy. In a state of desperation, I purchased a Realtek
>RTL8139 Family PCI Fast Ethernet NIC but that shows the same symptoms. I
>have also tried two other USB Wireless adapters from different
>manufacturers with exactly the same results.
>
>So, at the moment, if I want to use the Internet, LAN is disabled and
>then have to Enable the LAN connection to connect to the 2003 server.
>What a a pain !
>
>if someone can point me in the right direction I would be eternally
>grateful. :)

My guess(tm) is that you have a static IP setup for the wired ethernet
interface. Is this correct? If so, you probably have a tangled mess
of addresses, gateways, and routes for the two adapters to the router.

With XP SP2, the ethernet port takes priority over wireless. If you
plug something into the ethernet port, the "route metric" sets the
default route to whatever has the lowest number. Run:
start -> run -> cmd <Enter>
route print
or
netstat -r
with ethernet on and off and watch the settings change. Note the
metric column which sets the priority.

I wrote some drivel on the subject in the past:
<http://groups.google.com/group/alt.internet.wireless/browse_frm/thread/87de116db990c9be?tvc=1&hl=en>

Also see:
"An explanation of the Automatic Metric feature for Internet Protocol
routes"
<http://support.microsoft.com/kb/299540/en-us>

Also, note that the DHCP server (SBS 2003 ???) assigns different IP's
to the wireless and ethernet interfaces. If you have some kind of
security filter or obstacle course setup by MAC address, you might
want to verify if both adapters are properly configured. From your
description, they probably are correct, but it doesn't hurt to check.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558