Netpractice 42 Tutorial May 2026

Scenario: Two different subnets connected via a router. Client must reach a server.

Key: Client needs a gateway (router’s interface IP on its own subnet).

Example:

✅ Ensure each device's gateway is inside its own subnet and matches router’s IP. netpractice 42 tutorial

Scenario: One router, two networks. You are given limited IP ranges. Task: Split a /24 network into two /25 networks. Solution:

Common error: Using overlapping subnets. NetPractice will immediately flag this.

Between network ID (+1) and broadcast (-1): 10.0.0.33 to 10.0.0.46 Scenario: Two different subnets connected via a router

Why this matters in NetPractice: If you assign a host IP that equals the network ID or broadcast, the exercise will fail.

Different links must use different subnets. If two links use 192.168.1.0/24, packets will get confused. Keep them separate.

If you are a student at 42 School (or any of its global affiliates like 42 Wolfsburg, 42 Paris, 42 Berlin, or 42 Network), you have likely encountered a daunting, puzzle-like project called NetPractice. ✅ Ensure each device's gateway is inside its

Unlike traditional networking exams that rely on multiple-choice questions, NetPractice is a hands-on, interactive simulator. It presents you with a series of small networks, broken routers, and misconfigured IP addresses. Your job? Fix the routing tables and IP assignments to make the entire network communicate.

This tutorial will break down everything you need to know to conquer NetPractice, from the absolute basics of IP addresses to advanced subnetting techniques.

Sometimes you have multiple networks behind one router. Instead of adding three routes, add one summary route.