How Container Networking Works: Building a Bridge Network From Scratch
Begin with the basics to understand Docker and Kubernetes networking: learn how to create and interconnect Linux network namespaces using only command-line tools.
Discover
Tutorials, challenges, courses, skill paths, playgrounds, and more — search the whole library in one place.
How Servers Work: A Hands-On Introduction to TCP Sockets
Learn how servers actually work by building a tiny TCP server and client from scratch. A hands-on introduction to sockets, TCP, and the network programming model every backend, DevOps, and platform engineer should go through at least once.
A Practical Guide to SSH Tunnels: Local and Remote Port Forwarding
SSH port forwarding explained in a clean and visual way. How to use local and remote port forwarding. What sshd settings may need to be adjusted. How to memorize the right flags.
Block Unexpected Access to a Service on a Dual-Homed Linux Server
On a dual-homed Linux server, a service bound to one network's IP address may still be reachable from another network. Learn how to prevent this unexpected access without disrupting legitimate connections.
Reach a Linux Service Through an Interface It Doesn't Listen On
On a dual-homed Linux server, a service bound to the IP address of one interface may still accept connections that arrive through the other interface. Learn how to reach such a service through an interface it doesn't listen on, using a routing trick.
Connect a Container to a Service Bound to Localhost on the Docker Host
Learn how to access a service bound to localhost of the Docker host from a bridge-networked container, without exposing the service to the local network or disabling network isolation.
Connect a Container to a Service Running on the Docker Host
Learn how to access services running on the Docker host from a bridge-networked container, without hardcoding host IP addresses or disabling network isolation.
Computer Networking Fundamentals For Developers, DevOps, and Platform Engineers
A heavily illustrated introduction to the first two layers of Computer Networking: Ethernet and IP. A must for any developer or DevOps engineer who wants to build solid understanding of computer networking before they move to the higher-level protocols like TCP, UDP, and even HTTP.
Master SSH Tunnels: Local and Remote Port Forwarding
Learn how to reach an internal port on a remote machine from the local system, jump through a bastion into a private VPC, expose a development server to the Internet through a reverse tunnel, publish a home network device, and spin up a full-fledged SOCKS proxy with nothing but a regular SSH connection.
Master Container Networking
Do you want to troubleshoot container and Kubernetes networking issues like a true expert? This is a highly practical learning path that will take you from the basics of container networking like creating a network namespace, to more complex topics like configuring a bridge network and using iptables to set up network address translation (NAT) and port forwarding.
This playground was created by an iximiuz Labs user and is provided with no warranty.
Dual-Network Router Lab
Five Ubuntu VMs across public and private subnets, joined by a dual-homed router. The private subnet has no direct Internet access.