The Weird Case of the Modem that Would Work With Only One of the Devices Connected to It.

I received a message this morning from my brother, who said to be having problems with his modem. He said, that all the sudden all the devices connected to it stopped getting internet service, except for one. The devices seemed to be connected, but the internet would not work on any of them, except for the Roku they use to make their TV a little smarter. I said I would stop by to check it later, and so I did.

Just like he had explained, only the Roku could connect to the internet. My initial thought was that the Roku, for some reason was hugging the internet all for its own, so I disconnected it, and nothing changed. The other devices still were unable to connect to the internet. I knew for sure that the devices were connected and that the modem was recognizing them because I could see them in the modem’s settings panel.

I must have spent over half an hour looking at all the settings in the modem over and over, changing channels, and other settings with no luck. When I was about to give up, it occurred to me that it could be a DNS issue. This right after my brother demonstrated how WhatsApp was the only internet app that seemed to work. I updated the DNS in a Mac we had wired to the modem, and just as I hit the Apply button, a bunch of notifications and what not started showing up in the screen. Vioala!

I adjusted the DNS settings on the modem, and then all the connected devices started working well. I don’t know who his ISP is, and why in the world their DNS would stop working, but I’m glad there are open DNS servers. As far as for why the Roku was the only device that was working well, it seems Roku uses custom DNS.