Thunderbolt 3 dock – no network
I have a Lenovo Laptop P52s, connected to a Lenovo Thunderbolt 3 dock. Everything, LAN, video, USB keyboard, …, was working under Windows 10, but after installing Ubuntu 24.04 LTS the keyboard and LAN had problems.
Symptoms
- A Lenovo laptop works partially, forwards the image to the DisplayPort, but not LAN nor keyboard.
- The dock works perfectly on another Lenovo laptop with Ubuntu 24.04 connected to the Thunderbolt port, forwarding the DisplayPort, LAN, keyboard, power delivery.
- All drivers and firmware up-to-date
Solution
There is a setting in Ubuntu 24.04 LTS to allow the dock to connect the LAN to the computer. It’s under Ubuntu’s Settings / Privacy & security / Thunderbolt where I clicked “Allow thunderbolt” and it now works!
Note
After upgrading the system packages the dock may need to be authorized again.