Internet goes out if I plug in more than 2 ethernet cords in router?

jmflu

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Jun 5, 2012
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I have a Netgear wndr4300 router.

The following setup had been working fine for well over a year:

4 ethernet cords (2 of them are very long and go to other areas of the house)

The other day the internet randomly went out at around 11PM. I noticed that I still got internet when I went straight modem to computer. So I unplugged all 4 of the ethernet OUT cords from the modem and put them in one at at time.

The first 2 work fine as plugged in. I can even add a third. But if I plug the 4th one in, the wired and wireless internet both go out on every computer.

It is a specific cord (the longest one) that seems to cause this (altho it didn't the past year) - and the light on the router is orange as opposed to green like the other ones. (tho the manual just says "The LAN port has detected a 10/100 Mbps link with an attached
device.")

Any clue why this would be doing this? I am baffled.

I am done a hard reset on my router but same result.
 
Solution
Check for crimps in the cord.. Try that cord by it's self with another device..
If that cord works alone fine and then adding the other shorter good ones, it fails.. You prolly have a bad router.
You need to test that long cord.. imho
What happens if you plug just the longest problematic cord? What happens when you connect device at the other end to another cable? What happens when you connect another device and that cable' other end?

Change of color means that the router cannot negotiate faster network speed (eg 100mbps), and backs down to slower one (eg 10mbps). This could be caused by cable degradation / damage, or the equipment at the other end.
 

Yeah, that's the important question.

It sounds like the cable has developed a short, and two of the wires inside it are touching. If it's the right pair of wires, it would create a quasi-loop - everything the switch is sending on the Tx line (transmit) is also being received by the switch on the Rx line (receive). Smarter (expensive) networking equipment will recognize this condition and shut off ports to isolate the loop from the network. Cheap networking equipment will get confused and go crazy. Sometimes it still works but at a much slower speed. Sometimes it stops working entirely.

This is why companies pay the big bucks for high-end networking equipment, like $300 switches and $1000 routers. They don't want the entire company's productivity to grind to a halt because someone plugged in a bad ethernet cable causing the internal network to go down.
 

OhioLeda

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Dec 15, 2012
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Check for crimps in the cord.. Try that cord by it's self with another device..
If that cord works alone fine and then adding the other shorter good ones, it fails.. You prolly have a bad router.
You need to test that long cord.. imho
 
Solution

jmflu

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Jun 5, 2012
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Sorry for the late reply. So I plugged in the long troublesome cord straight from my modem and then into my laptop on the other side and it got the "no internet access" - so I think I can safely assume that there is some damage to the cord somewhere along the way. I think my plan is to get a new cord tomorrow and re-run it along the house and hopefully that fixes everything.

I will check back in after I try that.

Thanks for the responses everyone I appreciate it