Loopback adapter won't link on M4100-D12G ports
In the process of assisting a relative troubleshoot a new home Internet router, I was recording a video to demonstrate how to test a switch port with a loopback adapter. In the process, I discovered that I couldn't get a linked status on a M4100-D12G switch.
This port provides a connection for other network devices including a laptop and cameras.
I tried both a RJ45 and Gigabit loopback adapter and well as one I'd created myself.
All these loopback adapter work on a Netgear 5-port switch and a home router with integrated switches.
Is there an explaination of this behavior?