Resolved Weird Ethernet Issue on Mac Mini M1, help reproduce?

[aajeevlin]

Whenever I unplug and reconnect the Ethernet cable back into the Mac Mini M1, it will continue to connect/disconnect over and over until I reboot. It's usually resolved by a reboot. This is how I can reproduce it:

Open Network, and make sure the Ethernet connection is "Connected" and green. Unplug the Ethernet cable, wait until it says "Not Connected". Plug the Ethernet cable back, it will say "Connected" and after a couple second it will go to "Not Connected" and just continues this over and over until a reboot. Once a reboot is done, the connection is solid and the problem completely goes away.

Anybody having this issue? Or cared to try?

Update: looks like it was due to a software that I had installed. It was a network related software, it doesn't do much so I didn't realize it would have such weird affect. Thanks for the help.

 

[bernuli]

What happens if you power cycle the device on the other end of that Ethernet cable?

 

[aajeevlin]

What happens if you power cycle the device on the other end of that Ethernet cable?

Sorry I should add, I have only unplugged from the other end. The end that's connected to a switch. But I believe either end will produce the same result.

What do you mean by power cycle the device on the other end? Like power cycle the Mac Mini or the switch?

 

[bernuli]

Sorry I should add, I have only unplugged from the other end. The end that's connected to a switch. But I believe either end will produce the same result.

What do you mean by power cycle the device on the other end? Like power cycle the Mac Mini or the switch?

Power cycle the switch and see what happens

 

[aajeevlin]

Power cycle the switch and see what happens

Same result. I have also done this with another switch and about 3 other Ethernet cable. I first observed this when I plug in a new Ethernet drop for the room. I initially thought I did a bad job making the Ethernet cable. But it turns out it was the Mac Mini.

 

[bernuli]

Same result. I have also done this with another switch and about 3 other Ethernet cable. I first observed this when I plug in a new Ethernet drop for the room. I initially thought I did a bad job making the Ethernet cable. But it turns out it was the Mac Mini.

Sounds like could be auto negotiation problem. You could try setting hardware link speed in advanced.

I don’t have an M1 though us just guessing here.

 

[aajeevlin]

Sounds like could be auto negotiation problem. You could try setting hardware link speed in advanced.

I don’t have an M1 though us just guessing here.

Thanks I’ll look into that.

Just tried no luck. BTW, even if I just log out all user and log back in would also resolve the problem. Wonder if this is also a bad install.

 

[Fishrrman]

OP wrote:
"Whenever I unplug and reconnect the Ethernet cable back into the Mac Mini M1, it will continue to connect/disconnect over and over until I reboot. It's usually resolved by a reboot."

Reminds me of this:
Patient: Doctor, it hurts when I do this.
Doctor: Then... don't do that.

Is there a particular reason you need to keep plugging/unplugging the ethernet cable?

I might do this one time every 6 months, if even then...

 

[jeyf]

replace the ethernet cable and abandon the port on the switch/router

or

cycle power
un plug the mini
power everyting down, inc other computers printers etc
start with the fiber / cable modem power it up, all these deivces not fast so patience takes a few minuites
power up the switch/router box if seperate
power up the mini
re connectt to the switch/router
fixed?
power up other devices
fixed?

or

-if you have an iPhone download the network monitorl from Fling. Last time i cked it was free. this might give you some insidght a point of view form out side.
-the stwich/router likely has an internal routing table and maybe history status. log into its internal page at "admin" "default pw" ~ http://192.168.1.1