Strange LinkSys BEFSX41 Anomaly, Behavior - Working the Cause

[Hop]

BEFSX41 web interface is non-responsive, slow to offer the first page, and completely stops responding (the interface) trying to look at another page.

Please pardon me for the flood of information about my network. I believe in offering as much information as I can about the hardware I'm having an issue with. I hope I didn't omit anything.

I have a BEFSX41 LinkSys wired router with firmware 1.52.15, Jun 11 2007.
It does a pretty good job, doesn't lock up or need resetting, and doesn't reset on its own at all. My network knowledge is more advanced than the average user, but nowhere NEAR expert.

The BEFSX41 is a work horse for my LAN. I have it connected to a switch that handles three machines on its own, two additional machine connections, and a WAP that handles another wired connection to the WAP, and four wireless clients from the WAP. Every machine on my LAN is configured as static, for network activity logging. Having three teenagers on the network makes that very necessary! :shocked:

I wanted to experiment, so I bridged the wireless and wired NIC's in my laptop, and wire-connected a machine to my laptop, using the laptop to allow that machine to connect to my LAN network. I've always wanted to do that and this was my fourth attempt. The laptop is running Windows XP Media Center Edition, and the connected desktop via wire is running Windows XP Pro.

I had problems with the laptop losing connection to the LAN periodically and had to repeatedly repair the laptop's bridge, so I changed the desktop that is connected to a static IP instead of DHCP. That seemed to fix the issue, for what reason I have no idea.

The problem I was having is that the router's web interface was slow to respond to the main page, and became completely non-responsive when I tried to go to another page. During this problem, the router's performance was still OK. No decrease in throughput and was still pingable. After I cycled the router, I was able to get back into the web interface just fine, but after about an hour, the same problem repeated.

I've since unbridged my NIC's in the laptop, and the desktop is wired to a switch to the router, and the problem didn't resurface over a three day period of about the same network activity on the laptop and the previously connected desktop. Out of curiosity, I repeated the bridging, and connecting the desktop to my laptop again, and although both the laptop and the desktop can access my LAN, the problem reoccurred.

So I'm almost convinced the bridging and connecting strategy caused the router to act the way it did, but I'm at a complete loss as to why. In the future, I'd like to use this strategy to allow a machine without a wireless NIC to use my laptop to connect to my LAN, but not if it is going to freak out my router.

Has anyone had this problem and found a solution? Even the cause would be helpful so I can take steps to prevent problem.

Thanks for your time!

Hop

 

[spidey07]

My guess is you created a loop in your network. When this happens broadcast traffic keeps building up as it is never dropped until eventually the whole network slows to a crawl. All these broadcasts started taking a hit on your router processor until eventually it had to be reset.

Somehow you created a bridging loop. LANs must be completely loop free to function.

I'm sure this is what happened if you bridged your NIC and wireless card and had both connections active.

 

[Hop]

Originally posted by: spidey07
My guess is you created a loop in your network. When this happens broadcast traffic keeps building up as it is never dropped until eventually the whole network slows to a crawl. All these broadcasts started taking a hit on your router processor until eventually it had to be reset.

Somehow you created a bridging loop. LANs must be completely loop free to function.

I'm sure this is what happened if you bridged your NIC and wireless card and had both connections active.

Interesting. I'll research that issue to see how to prevent the cause.

The only thing that deviates from your diagnosis is that although the web interface became unusable, the throughput to all the clients seemed to be unaffected. I pushed this theory to over a full day of use post-web interface failure. Downloads were still pushing up to 15mbps, web browsing was still speedy, my son didn't seem to notice any increased latency playing World of Warcraft, and ping and speed tests to remote servers appeared nominal. During this whole day, the web interface was non-functional. I even did a shields up invasive test of the stealth of my network from the internet, and the results were the same there too, telling me the firewall was still functional. I had to do that because that worried me big-time.

 

[spidey07]

I'm just saying bridging connections can yield to all sorts of "weird" things happening if you don't fully understand what the bridge is doing and what the paths are. Since SOHO routers/switches don't do any sort of loop protection (spanning-tree) it's very easy to create a loop.

 

[Hop]

Originally posted by: spidey07
I'm just saying bridging connections can yield to all sorts of "weird" things happening if you don't fully understand what the bridge is doing and what the paths are. Since SOHO routers/switches don't do any sort of loop protection (spanning-tree) it's very easy to create a loop.

Yes, thank you. You have given me some things to research and learn about. I didn't know what SOHO meant, Small Office/ Home Office. Always wondered about that. Looking at bridging loops now on Google. Lots to read about that. It's becoming apparent that the first college course I should take is about networking.

 

[JackMDS]

It might be a combination of small things that are beyond simple control.

I hope that you are referring to Bridging and did not switch On ICS. ICS would cause double NAT.

You need to use static IP cause there is No DHCP in the second Network (the Laptop wired card and the computer connected to it have to be configured as a separate Network before Bridging) after Bridging they join the network with a bridged IP and the Routing is done by the main Router.

This page shows nicely the Bridging process, it is Not exactly your scenario but it is easy to extrapolate the principles.

http://www.windowsnetworking.c...utorials/wxpbrdge.html

BTW, I never used Media center as the Briding agent, but I know that the OS media extensions it are Not very ?smooth? when it comes to Networking. I.e. it could be that with pure WinXP Pro it would work better.

Wireless is a little quirky too when coming to support unorthodox arrangements.

As Spidey mentioned above Entry Level Network Hadrware is Not really thoroughly tested and supportive of all the network capacities that are more prevalent in large business Networks.