No internet connection after ubuntu server 20.04 install, ifconfig not available

I recently installed Ubuntu Server 20.04 LTS on my desktop, and found out there was no internet connection even though I had the LAN cable connected. ifconfig and iwconfig failed saying the corresponding packages net-tools and wireless-tools were not installed.

EDIT

Here is the info requested. Please find the image here.

Solution 1:

Networking in Ubuntu server is managed by netplan. Your file lacks the details needed to connect the ethernet properly.

First, let's rename the file:

sudo mv /etc/netplan/*.yaml  /etc/netplan/01-netcfg.yaml

Now, let's change it to include the required details:

sudo nano /etc/netplan/01-netcfg.yaml   

Change the file to read:

network:
  version: 2
  renderer: networkd
  ethernets:
    ens33:
      dhcp4: true

Netplan is very particular about spacing, indentation, etc. Proofread carefully twice. Save (Ctrl+o followed by Enter) and exit (Ctrl+x) the text editor. Follow with:

sudo netplan generate
sudo netplan apply

You should be all set.

Solution 2:

A short addon to chili555's answer: In my case, the only problem was that for some strange reason, Ubuntu believed my network interface name in /etc/netplan/01-netcfg.yaml to be enp0s5 instead of enp0s4 which was the correct for my VM.