Why is my Ethernet or Thunderbolt connection not working?
PC-to-Mac Mode: Connect via Ethernet Only
If you are using Luna in PC-to-Mac mode but are unable to establish an automatic connection using an Ethernet cable, here are some steps to take to ensure that Luna connects via Ethernet only, instead of Wi-Fi.
In the Luna PC app, click on the "☰" icon and click on Preferences. In the Connectivity tab, under "Allowed Non-USB network interfaces" choose "Allow any network interface (default)" as your preferred connection method.
Then quit both Luna apps. Connect your devices with an Ethernet cable. Once both devices are connected, launch both Luna apps. You should see that your connection type is indicated as Ethernet on the Luna primary app (as seen below).
Mac-to-Mac Mode: Connect via Ethernet or Thunderbolt Only
Troubleshooting the Ethernet Connection
Troubleshooting the Thunderbolt Connection
Troubleshooting Your Ethernet or Thunderbolt Connection
Luna should connect automatically if it detects an active Ethernet or Thunderbolt connection between your Macs. You can also adjust Luna's settings so that Luna will only connect over an Ethernet or a Thunderbolt connection, instead of Wi-Fi.
In your Mac's top menu bar, click on Luna Display then Preferences. In the Mac-to-Mac tab, change "Allow any network interface" to your preferred connection method: Connect via Wi-Fi only, Connect via Ethernet only, or Connect via Thunderbolt only.
Troubleshooting the Ethernet Connection
On your primary Mac, open Network Preferences by going to System Preferences > Network, or by clicking on the Wi-Fi symbol in your Mac's top menu bar and selecting "Open Network Preferences". In the left side menu, select USB/LAN.
If your devices are connected via Ethernet, the Status will change to Connected and the left side menu panel will either say "Connected" or "Self-Assigned IP" under the USB/LAN option. You will need to check this setting on both your primary and secondary devices to confirm that the Ethernet connection was set up properly.
More Ethernet Connection Troubleshooting
- Make sure both ends of the Ethernet cable are fully connected to each Mac, router, or access point.
- Restart your Macs, router, or modem.
- Create or switch to a new network location on your Mac.
For more help, check out Apple's support article for troubleshooting an Ethernet connection on a Mac.
Troubleshooting the Thunderbolt Connection
A Thunderbolt bridge needs to be established between your Macs before Luna can connect using a Thunderbolt connection.
On your primary Mac, open Network Preferences by going to System Preferences > Network, or by clicking on the Wi-Fi symbol in your menu bar and selecting "Open Network Preferences". In the left side menu, select Thunderbolt Bridge and ensure that Configure IPv4 is set to "Using DHCP."
Once your primary Mac detects that it is connected to your secondary Mac, an IP Address will be shown in the IP Address section. The connection status on the left side menu panel will also change to a yellow dot and be labeled as "Self-Assigned IP." You will need to check this setting on both your primary and secondary devices to confirm that the Thunderbolt connection was set up properly.
More Thunderbolt Connection Troubleshooting
- Make sure both ends of the Thunderbolt cable are fully connected to each Mac, router, or access point.
- Ensure your cable is Thunderbolt-compatible.
- Restart your Macs, router, or modem.
For more help, check out Apple's support article for troubleshooting a Thunderbolt connection on a Mac.
Can adapters be used for wired connections between devices?
How do I use a USB, Ethernet, or Thunderbolt connection?
Yes, adapters can be used for wired connections, such as Thunderbolt or Ethernet cables. This is recommended if your devices have incompatible port types. Using adapters for wired connections is different than using an adapter to plug your Luna unit into your computer. You will still need to plug the Luna Display hardware directly into your Mac or PC, even if you are using a wired connection.
For example, let's say you are using a 2015 iMac as a secondary display for your 2021 MacBook Pro and would like to use a Thunderbolt cable to connect your devices (instead of using WiFi). The 2015 iMac has Thunderbolt 2 ports (mini DisplayPort), while the 2021 MacBook Pro has Thunderbolt 4 ports (USB-C). You will need an adapter in order to use a Thunderbolt cable between these devices. In this instance, we would recommend using a Thunderbolt 3 to Thunderbolt 2 adapter with a Thunderbolt 2 cable.
In another example, using the same devices as above, let's say you'd rather use an Ethernet connection between these devices. The 2021 MacBook Pro does not have an Ethernet port, while the 2015 iMac does. You would need an Ethernet to USB-C adapter in order to utilize an Ethernet connection between these two devices.