Basic Network Setup Using 2 Linux VMs

Networking Basics Lab 🖧

This project demonstrates a basic networking setup using VirtualBox, Ubuntu Desktop, and Ubuntu Server. It covers VM setup, VirtualBox networking configuration, IP configuration, testing, and troubleshooting.

Lab Topology 🖼️

This is a simple flowchart explaining the Network.

1. Lab Setup ⚙️

VirtualBox Network Configuration

• Created a Host-Only Adapter in VirtualBox:

  • IPv4: 192.168.56.1

  • Netmask: 255.255.255.0

  • DHCP: Disabled (because we use static IPs)

Added two VMs:

• Ubuntu Desktop VM

  • Adapter 1: Host-Only Adapter

• Ubuntu Server VM

  • Adapter 1: Host-Only Adapter

2. Network Configuration 🖧

Ubuntu Desktop (192.168.56.10):

network:
  version: 2
  renderer: NetworkManager
  ethernets:
    enp0s3:
      dhcp4: no
      addresses:
        - 192.168.56.10/24
      gateway4: 192.168.56.1
      nameservers:
        addresses: 
		- 8.8.8.8
		- 8.8.4.4

Here you can see how we edit the Netplan Config in Desktop using (nano).

Screenshot from Netplan config being edited with nano

Ubuntu Server (192.168.56.11):

network:
  version: 2
  renderer: networkd
  ethernets:
    enp0s3:
      dhcp4: no
      addresses:
        - 192.168.56.11/24
      gateway4: 192.168.56.1
      nameservers:
        addresses: [8.8.8.8, 8.8.4.4]

Here you can see how we edit the Netplan Config in the server file using (nano).

Here i applied the netplan and it prompted us with (Warning).

Screenshot from Desktops’s CLI

Screenshot from server’s CLI

We fixed it by removing write (w) permissions from group and others .

Permission Warning Fix

Testing ✅

Ping from Desktop to Server:

ping 192.168.56.11

Screenshot from desktop’s Terminal

Ping from Server to Desktop:

ping 192.168.56.10

Screenshot from Server

Both pings are successful.

Troubleshooting 🔧

PROBLEM 1

(Issue): No IP address on enp0s3.

Screenshot from Desktop’s Terminal

(Fix): Configured static IP in Netplan and applied it with sudo netplan apply.

. Screenshot from nano

(Result): Problem fixed.

Screenshot from nano

PROBLEM 2

(Issue): Could ping from server to desktop but not the other way

(Fix): Assigned consistent static IPs to both machines to avoid conflicts, turned dchp off. (previously server had .101).

Lessons Learned 📚

• How to configure static IPs with Netplan.

• How to troubleshoot connectivity using ping and ip addr show.

• Importance of consistent network settings in VirtualBox.

Future Work 🔮

• Add DHCP server to the lab.

• Test routing between multiple networks.

• Automate network configuration with Ansible.