Bizzare network problems

[Alyosha]

Beginning friday my network has been acting up. I've got about 20 users running off of a clark connect rounter, 2 16 port linksys switches, an 11Mb wireless AP and a couple odd switches in people's rooms.

Our connection was up and down throughout the day and I thought it might be ISP issues, but discovered it was not when I could not even log into the router. The loss of connection begins sporadiclly and gets worse untill I can't log in at all unless I re-boot, un-plug/re-plug, do a little dance and say a chant..., that is to say, I don't know why it stops working and why it re-starts. I ran mem-test and got a single memory error, tried switching RAM sticks but got the same problems. Ran hard drive diagnostics but found no problems. Tried swtiching NICs and cables but always got the same problems. I'd be up for a few minutes but then fall into random wierdness.

Now, for some paranoia. As I look through the router logs I believe I'm seeing DHCP requests from computers not in our house. BTW, my house is big frat house (though we're not a frat, but that's niether here nor there) with lots of houses right near us. My wireless signal is encrypted, and I kinda doubt any of the sororities adjacent to us are going to be hacking my wireless but who knows.

As I look closer, there are definately rouge computers on there, could that cause any problems? More specificlly, if someone was had a wireless router repeating my AP signal, could that screw anything up? I ask this as sometimes when I re-start the router, as it tries to initialize the LAN ethernet card it gives me an error saying, "some other host already uses 192.168.1.1" as if some other router were trying to control my network. I'm not sure if that's possible but I'm stumped.

Any insight is greatly apprceciated.

 

[Alyosha]

More info:

Just changed every password and enabled every security feature on the AP and things are seeming more stable already, but that doesn't mean much yet.

Also, looking through my router logs I find that my external NIC is entering promiscuous mode at startup. I don't entirely know what that means, but that doesn't seem right. Should I be worried here?

 

[Alyosha]

Ok, I'm going to quit saying I think its working because every time I do it quits working again.

In the continuing saga of wierdness, as I look through more logs I keep seeing a DHCP request from "MN-740". Its doing so on different IP addresses and different MAC addresses, including the MAC address on my machine as well as a couple other machines in the house here. Upon googling MN-740 I find that that is the name of an X-Box wireless adapter.

What does this mean? Is this just a coincidence, or is some device spoofing IP and MAC addresses trying to screw with my network? It been doing it almost constantly for the past 24 hours, though probably longer as my logs only go back to yesterday and my most recent re-install.

I'm stumped, anyone have any ideas.

 

[Alyosha]

Ok, I'm just going to keep answering my questions.

The reason I'm asking (besides that it OUGHT to be configurable from other than an Xbox console) is that, every so often, the adapter seems to lose the ability to speak TCP/IP to anything other than my LAN (192.168.x.x) - it apparently drops the gateway. I can still see all the file shares I have on the LAN, just can't reach the gateway or anything on the external Internet.

Quoted from here
Some people asking if you could make an x-box wireless adapter work with a computer because it was interfearing with his wireless network and causing the exact same sypmtoms as I'm having.

I think my problems may be solved now. But I've said that before.

 

[HTPC Rookie]

The random up / down could be caused by nothing more than a 2.4Ghz phone nearby overpowering the wireless. But with the other symptoms you describe it sounds more complicated than that.

Can you run a UTP cable directly from the box that's losing connectivity to your router (not use wireless at all)? That would at least narrow it down to being the wireless for sure.

If after trying the UTP you decide it is the wireless, every WAP I've seen comes set to channel 6 out of the box. Maybe try changing yours to 1 or 11. Not sure if it's true or not by I hear the only true seperation on .11b are between channels 1,6, and 11.

Then there's going on ebay and getting a .11a only setup. It sucks for range, but so few people use it interference is not as likely, and cordless phones etc. don't bother it. If you're close to the WAP the short range may be a good thing, less likely someone even a few rooms away can pick it up.