Or a WAP (LAN port)?
It matters. I offer no support when a second router is a router. Google "How to use a router as a WAP"
So i'm on a two floored building, with the main cable modem, and router being on the first floor, a while back i bought a very long cat 6 cable(100ft) i believe to connect to the top floor to a secondary router i was just using as an extender. It had been working fine for all this time until a few weeks ago.
Now it doesn't give connectivity to the router, i changed multiple routers upstairs with the same issue, and also changed the ports on the router on the first floor. Periodically the light will flash on the upstairs router, but without any internet connectivity. When i take the said router downstairs to test it on other cables it works flawlessly. So obviously there must be an issue with the cable right, but here's the hitch, when i plug in the cable directly to the upstairs desktop it works fine with perfect connectivity.
So i'm really stumped as to why the cable would work fine with a desktop but has issues with other routers setting up a network, does anyone have any idea why?

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