On 2/27/21 4:56 PM, Doug H. wrote:
On Sat, Feb 27, 2021, at 4:36 PM, Samuel Sieb wrote:
Do you have a network switch of some kind around? If so, try putting that in between and see if it makes any difference. It it does, then there might be something to try with ethtool.
I do. Netgear FS116 Fast Ether switch.
This will also help to flesh out what Ed was asking about...
While up and working I added the switch in the middle. Worked fine, the connection came right back up once both hosts were plugged in.
This also gave me better visibility to the state during boot (the Ed questions). While booting the 10M light was on and this is the light that remained on all the way to the grub menu. I did hold there to make sure it was stable and then set a timer to see how long before the lights go out once I hit <enter> to select the kernel. That was 8 seconds.
But then comes the kicker...
This time the link came back up (as it used to, working at 100M) and it was working fine by the time Xfce was up I was able to check. So this issue does not seem to effect my setup if passing thru a switch.
So this confirms what I was suspecting. The 10M you see at first is the "default" state of the ethernet card where it's watching for the wake-on-lan signal. Once the kernel boots and initializes the card, the card tries to auto-negotiate. This seems to be failing due to some interaction between the pi's network device and this one.
One thing to try if you can is to use a cross-over network cable.
It would have been helpful to see what the output of ethtool is when it's working, but when it's not working, try the following:
ethtool -s enp5s0 mdix on
Give it a few seconds, see if it comes on. If not, then try:
ethtool -s enp5s0 mdix off