I can confirm fix-switch seems to work reliable - kudos to adminX! I’ve just finished power cycling stress test (about 30 reboots) of my setup because of hunting unrelated bug and fix-switch recovered ethernet connection every time (before that there was about 80% probability ethernet ports will NOT work after reboot).
Maybe warning for someone who is using SFP modules like me. Fix-switch will not work until you stop sfpswitch.py service and temporarily force eth1 to the copper mode (you can use sfpswitch.py code with variable force_mode=‘phy-def’). It’s because MDIO bus is not accessible when eth1 is in SFP mode.
PS: I’ve also tried to fix things more permanently by writing to eeprom attached to the switch, but it turned out it is write protected (R130). Desoldering resistor would need physical access to the router, something that is currently not easily possible, maybe someday in spring…