Ubuntu 19.04, 5.0.0-32-generic x86_64.
My (geriatric, I know) onboard atl1 ethernet chip is getting extremely hot, even temporarily fails (until reboot), when heavily networking at 1000 MB/s. Tried to reduce speed to 100 MB/s with both the nm- app and nmcli which worked and was saved to /etc/NetworkManager/system-connections/netplan-enp3s0.nmconnection (amongst other files in there).
On next boot, the NIC is back to 1000 MB/s, obviously - according to journalctl - using /run/NetworkManager/system-connections/netplan-enp3s0.nmconnection and running into a conflict:
keyfile: cannot load /etc/NetworkManager/system-connections/netplan-enp3s0.nmconnection due to conflicting UUID for /run/NetworkManager/system-connections/netplan-enp3s0.nmconnection (6effa1b1-280b-3785-9b52-c723b445fb3e,"netplan-enp3s0")
The UUID of the two files is identical.
Other setting made and saved with nmcli, like IP4 address, are being adhered to and reused on reboot. Admittedly, those could come fron netplan. Unfortunately, NIC speed cannot be defined with netplan.
What is strange is I can't get rid of the connection in /run/..., even after deleting all files in /etc/... a (default?) connection in /run/... comes up on reboot and conflicts with the ones in /etc/... (if existent).
Searching the entire file system beyond {run,etc,lib} for default settings didn't give me any hints.
I think I've done my bit searching this and other sites, reading man pages and pertinent and similar articles, but I'm out of ideas right now.
