Hi. I connected a host PC with a raspberry Pi. An Ubuntu runs on the host PC and a busybox runs on the Pi without DHCP.
So I set the Ubuntu should share its own Ethernet connection. Cause the option "make available to other users" is set in default.

Then I set the static IP on the PI. And the gateway(The IP of the host PC).

So I can ping the host PC, but when I tried to ping google DNS: 8.8.8.8. It says：
12 packets transmitted, 0 packets received, 100% packet loss

I am bit confused. what else should be done?

Go to the Ubuntu network manager settings, and edit the Wired Connection. Go to IPv4 settings, and change the connection method to "Shared to other computers".

Then, on the Raspberry Pi, make sure to set a static IP in the range defined by the host PC's shared internet connection settings (if you don't know what these are, then set it to 10.42.0.2 - you can replace "2" with a number between 2 and 254). For the gateway, set it to the host PC's wired connection IP address, not the IP address it is using on its WiFi connection (or other ethernet device). If you don't know what this is, then it is 10.42.0.1

Basically, the "Shared to other computers" connection method turns your computer into a simple router. In older version of Network Manager, there was no configuration possible on this - it invariably used 10.42.0.1 as the local IP address with a subnet of 10.42.0.X. In current versions, you can optionally set a different IP address and subnet.

hi Issac, I think I missed one thing. In my version of Ubuntu, there's no such option as "Shared to other computers"
Under iPc4 setting, there's only User this connection only for resources on its network. I do not know if it means the same?

Idk GUI, but does the Ubu box get to the internet by wifi (or other wired nic)?
If so, maybe you need the kernel setting of ip forwarding, to act as router.
(For more details, web-search fastest) tcpdump to debug

What version of Ubuntu are you running? Make available to other users is not the same thing as connection sharing.

Does your Network Manager look similar?

https://askubuntu.com/questions/1694...wired-ethernet

Hi. my ubuntu is 17.4 and it looks quite different from this. This is also what made me feel pretty weird.

oh. I am not ready for the kernel compilation. I mean I thought the PC version should have already enabled enough options for me....

While the applet is updated the settings as described in the link should still be the same.

So I assume that your host PC is wireless and that you want to share the internet via its ethernet connection.

Does the Pi have a defined route?

The PC is connected to the internet via Ethernet and the connection between Pi and PC is a USB-Ethernet.
The Pi does not have DHCP and I just set the static IP of the Pi and the IP of the USB-Ethernet of the PC under the same sub-net. So I can ping the Pi from the PC and vise versa.
But I cannot let the Pi share the internet of the PC.

When you edit the connection settings for the USB ethernet under IPV4 is there a method pull down menu like in the link I posted?

Nope. This is also the thing that confused me for long. Cause before I post this, I've already searched for it. But in my case, there's no such option...

Interesting. I ran standard Ubuntu 17.4 as a Virtual Machine with a USB ethernet adapter and it was just as described. My connection naming will be different then yours and I did not actually configure it for sharing.

I'm not sure if this is what's needed, but here's what I thought of:

echo 1 > /proc/sys/net/ipv4/ip_forward

https://askubuntu.com/questions/2273...ard-ip-packets
https://unix.stackexchange.com/quest...-ip-forwarding