Xfinity cable modem/wifi router combined
Can anyone at Comcast Support answer a question for me? I have a recently-acquired (last week) Comcast cable modem with WiFi built in. An enormous, heavy modem, compared to past modems! When I plug in my 8-port ethernet switch, the modem transmits a clean relatively fast internet signal to all 8 ports. The small LED beside the modem ethernet port is green. When I plug in my 4-port ethernet switch to one of the modem ports, the small LED on the other side of the port is red. Thinking the switch was bad, I tried another 4-port switch of another brand, and it displayed the red LED. Then I tried a 3rd switch, and it displayed the red LED. Do I think all 3 switches are bad? Heck No! Also, interestingly I can get a clean internet signal (using a laptop to test) out of all 3 switches in spite of the red LED.
Can anyone tell me what that red LED is trying to tell me? There were no instructions with this modem except the self-install, which didn’t work anyway, requiring assistance from a telephone support person. If there is a link to detailed instructions regarding this modem, with details of the output from each of the ethernet ports on it, send me that.
By the way, I’m still not certain that Comcast has not disabled my personal modem (Arris SB8200, recommended by Comcast!). They have done it twice before, claiming I hadn’t given them the MAC ID. I had, THREE times!