Raspberry Pi - No Ethernet Caused By Charger
I was using a cheap USB charger, but I couldn’t get my Raspberry Pi to connect over Ethernet. The ethernet lights showed no link.
Turned out the charger couldn’t supply enough current. The Model B needs a 5V micro-USB supply that can deliver at least 700mA for the board alone, and more with anything plugged in; plenty of phone chargers only put out 500mA. When the Pi undervolts it shuts off its USB ports to stay stable, and on the Model B the Ethernet runs through that same USB chip, so it drops right along with them. Swapping in a Motorola OEM charger fixed it. I have the Model B, Rev 2.0 board with 512MB RAM.