When shall the amber LED lit on the network interface card? When your speed is 1000Mb/s?
On my PC Engines APU1d it´s lit when the speed is 100Mb/s.
Can I change the configuration so it is lit when the speed is 1000Mb/s?
The ethernet interfaces are Realtek RTL8111E. By default the r8169 drivers are loaded.
I have tried r8168 drivers, https://github.com/BROBIRD/openwrt-r8168, but it´s the same result.
It turned out that the RTL8111E support configurable LEDs.
I modified the r8168 driver so I got what I want.
The green LED is lit for link, all speeds, and flashes for network activity, for all speeds. The amber LED is lit for link 1G speed.