Ubuntu 20.04 LTS (Server) - Rerun Installer Network Setup

Solution 1:

A little more poking and help from a friend and we figured it out.

Although I had tried editing the /etc/netplan/00-installer-config.yaml file, I didn't know I had to run sudo netplan apply before it would take effect.

So the solution in summary is as follows:

1. Open /etc/netplan/00-installer-config.yaml:

   sudo nano /etc/netplan/00-installer-config.yaml
   

2. Edit the file to read as follows:

   #This is the network config written by 'subiquity'
        network:
          ethernets:
            eth0:
              dhcp4: true
          version: 2
   

3. Exit (Ctrl+X) and save (Write buffer? Y, Enter).

4. Now apply the configuration:

   sudo netplan apply
   

5. Restart.

   shutdown -r +0
   

On restart, ip a will show a working eth0 connection and ping 8.8.8.8 works!