Fixing WSL Ubuntu Setup & Hostname Issues • Farros

With Windows Subsystem for Linux (WSL), running a Linux environment on Windows is no longer complicated. The setup is usually smooth until a small configuration detail, like a hostname mismatch, suddenly throws an unexpected and confusing error such as:

alt text

sudo: unable to resolve host <hostname>: Temporary failure in name resolution

bash

In this guide, I’ll walk through:

Installing Ubuntu on WSL
Setting it as the default distribution
Creating a proper user
Changing the hostname cleanly
Fixing the “unable to resolve host” error
And finally: why I use WSL instead of Kali Linux in VirtualBox — including the downsides.

1. Installing Ubuntu on WSL#

First, check existing WSL distributions:

wsl -l -v

powershell

If Ubuntu is not installed:

wsl --install -d Ubuntu

powershell

After installation completes, launch it:

wsl

powershell

or open via windows start.

You’ll be prompted to create a default Unix user account. Choose a clean and professional username (for example, your GitHub handle). This becomes your Linux home directory:

alt text

/home/yourusername

bash

2. Setting Ubuntu as Default#

If Docker Desktop is currently your default WSL distro:

wsl -s Ubuntu

powershell

Verify:

wsl -l -v

powershell

The asterisk (*) should now be next to Ubuntu.

3. Changing the Hostname Properly#

To rename your machine, example:

sudo hostnamectl set-hostname sec-lab

bash

Restart WSL:

wsl --shutdown

powershell

Reopen WSL and your prompt should look like:

username@sec-lab:~$

bash

4. Fixing the “Unable to Resolve Host” Error#

After changing the hostname, you may see:

sudo: unable to resolve host sec-lab: Temporary failure in name resolution

bash

This happens because /etc/hosts still contains the old hostname.

Edit it:

sudo nano /etc/hosts

bash

You might see:

127.0.0.1    localhost
127.0.1.1    Old-Hostname

bash

Replace the second line with, example:

127.0.1.1    sec-lab

bash

Save, then restart WSL:

wsl --shutdown

powershell

The error should now be gone.

Installing Essential Security Tools#

After setup, install a minimal but powerful toolkit, like:

sudo apt update
sudo apt install -y \
curl wget git unzip \
net-tools dnsutils \
nmap python3-pip

bash

Why I Use WSL Instead of Kali in VirtualBox#

Many people in cybersecurity default to Kali Linux inside VirtualBox. I did too. But over time, my workflow changed.

Here’s why I prefer WSL for daily use.

1. Performance#

WSL 2 runs with near-native performance. No heavy VM overhead. No manually allocating RAM and CPU.

VirtualBox always feels heavier.

2. Workflow Integration#

WSL integrates seamlessly with:

Windows filesystem
VS Code
Docker
Git
Windows Terminal

You can develop in Windows while running Linux tools in parallel smoothly.

3. Minimalist and Intentional#

Kali comes with hundreds of preinstalled tools.

WSL + Ubuntu forces you to:

Install only what you need
Understand your environment
Build your own stack

That’s better for learning and discipline.

But WSL Is Not Perfect (The Cons)#

In security communities, WSL often gets criticized and many of it is valid.

Here are the most common concerns:

1. Limited Hardware-Level Capabilities#

WSL does not support:

Native Wi-Fi monitor mode
USB wireless injection
Direct hardware access like a real Linux system

If you’re doing wireless attacks or hardware exploitation, Kali in a VM or bare metal is still necessary.

2. Networking Quirks#

WSL networking can be confusing:

Changing IP addresses
Port forwarding edge cases
localhost behavior differences

It works but sometimes troubleshooting feels non-intuitive.

3. Not Fully Isolated#

A VM provides clear isolation from your host OS.

WSL is more integrated. That’s great for productivity, but:

Mistakes can affect your Windows filesystem
It’s not as sandboxed as a traditional VM

For risky malware analysis, a dedicated VM is safer.

Final Thoughts#

To be honest, I prefer Linux.

If I had the choice, I would run Linux as my primary system. I appreciate its philosophy, control, and engineering mindset. However, professional demands often require Windows, and that’s where WSL becomes a practical bridge.

WSL is not a full replacement for native Linux or Kali in a VM, especially for hardware-level testing or isolated lab environments. But for development, automation, CTFs, and daily security work, it provides a fast and efficient workflow.