If I unplug my Ethernet cable when the HE is up and running, then plug the cable back in, the port seems dead (no link light on the switch). I have to power cycle the HE to get it working again. This is a pain if I need to move some patch cords around or power cycle my switch.
My brother also has an HE, his doesn't have this problem.
If I boot up the HE connected to the switch (only), I get a link light on the switch (no router in the picture). If I unplug the ethernet cable and plug it back in, there is no link light. Also tried several different brands of switches... no luck. The link light on the switch indicates that the physical layer is connected(10/100/1000), it doesn't have anything to do with DHCP or the router.
Haha.. I have a 16-port switch, and in all reality, I hardly ever unplug or power-cycle the switch... but the HE has backup power and the switch does not, so it's a bad combo.
My Ubiquiti Unifi switch allows me to program some settings to each port of the switch. The port that goes to HE I turned off auto-negotiate and set it to 100 FDX. After doing this, I can unplug and plug my HE ethernet cable and it comes back online every time.
So the root cause seems to be something with the HE auto negotiate.
Side Note: Hubitat hasn't gotten back to me on this issue... I've sent them three emails over the last several months with no reply. I love my Hubitat, but concerning that they are not responding.