Question Ethernet connected laptop, PC, lose connection; Wifi devices don't

Aug 1, 2022
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I am trying to troubleshoot some internet connection issues that have been ongoing for about a year now. The gist is that, after some period of time, my Ethernet connection computers (Windows 10 PC, MacBook Pro, Mac Mini) lose their ability to connect to the network over Ethernet. When this happens, they can usually re-connect via Wifi (though sometimes not).
When this happens, other Wifi devices on the network appear to be mostly unaffected, though sometimes other laptops on the network also start having difficulty connecting.
Mobile devices (Android, iPhone), also sporadically stop being able to connect to the Internet over Wifi, but its not clear if this is the same issue that the Ethernet devices are having.

Setup;

  • Verizon FiOS ISP (300Mbps up/down) + FiOS ONT
  • Netgear Nighthawk R7000 router
on Ethernet Switch #1;
(TP-Link 5 Port Gigabit Ethernet Network Switch | Ethernet Splitter | Sturdy Metal w/ Shielded Ports | Plug-and-Play | Traffic Optimization | Unmanaged (TL-SG105),Black )

- custom PC
(mobo: Asus ROG Strix B550-F Wifi https://rog.asus.com/us/motherboards/rog-strix/rog-strix-b550-f-gaming-wi-fi-model/ )

- 2015 MacBook Pro + Amazon Basics USB3 Ethernet adapter
(https://www.amazon.com/gp/product/B00M77HMU0/ )

- 2012 Mac Mini

on Ethernet Switch #2;
(the same TP-link switch but 8-port model TL-SG108)
  • Nvidia Shield TV (2015)
  • HP Laser Printer
on Wifi;
  • Android phone
  • iPhones
  • iPad's
  • game consoles
  • Chromecasts
  • Google Home devices
All together there are ~30 devices on the network.

After some period of time, the devices on Ethernet Switch #1 all seem to lose their Ethernet connection. They no long show up in the "Attached Devices" on the router login page. My MacBook Pro, for example, gives the error message;

"<device> has a self-assigned IP address and will not be able to connect to the network"

Windows PC also has similar error, about being connected to the network but not having Internet access.

Some really confusing things;

  • none of the Wifi devices get kicked off the router like this
  • the MacBook Pro and PC can usually get back onto the internet via Wifi, but this is not ideal since I need to move big files between them on the network
  • the MBP, PC, Mac Mini, can still communicate with each other (???) despite not actually having router-issued IP addresses... somehow? Its not clear what connection is being used for this, but for example, my Mac Mini does NOT show up anywhere in the router's attached devices right now, yet I can still ssh into it from my MacBook Pro as usual (command: ssh username@macmini.local), and I can also see the Mac Mini and its volumes under the Server tab in macOS Finder
  • after I reboot my MacBook Pro, PC, etc., the devices are still unable to get an internet connection on the network, or any router-assigned IP. So the problem persists between device reboots
  • if I reboot the router, the issue usually (usually.....) goes away ; problem with this is that these days I dont even notice the issue until I am logged in to Work From Home and am in the middle of doing work that prevents me from resetting the router!
I have the latest firmware on the router. The router is set to run its own DHCP server (from .2 up to .254 as usual). I have logging enabled in the router, and I have copied all the logs and looked through them. There are no errors of any kind being reported. I can see that, for example, the MacBook Pro was connected via Ethernet two days ago from the log messages. However its since disappeared. There's no message about it (or any devices) being disconnected.

I have been Googling this for weeks and the best thing I can come up with is that the router's DHCP server is crapping out... but only for Ethernet devices... but I cant find any way to check the actual status of DHCP on the router. The router login page always says "everything is good". Never any issues reported there. One the router itself, I often see the LED for the "1" LAN connection turned orange, but not sure what problem this is suggesting? Again, no error codes anywhere. Also worth noting that every time I reset the router, I lose all the log messages its built up... so that does not help the situation.

Any suggestions would be appreciated. I am close to just buying a new router, but I know this Nighthawk R7000 really should be able to handle this, and it does handle all the workloads just fine when this connection error doesnt crop up.
 
Last edited:
Aug 1, 2022
8
1
15
well feeling kinda dumb now but right after posting this I realized that all the affected devices are on the same network switch (TP Link TL-SG105)

just pulled the power on the switch, plugged it back in, all devices immediately back on the network with Internet access and showing up again in the router device list

so I guess the question now is, why would this be happening?? Has the switch gone bad? Its only a year old.
 
Those switches tend to be fairly solid. Like anything they can fail. Most times a switch just stops passing data when it breaks. I would check the power supply and make sure it is putting out the proper voltage id you can.

If it keeps happening that switch is pretty cheap to replace.