Paths

A guided order through the catalog. Pick a destination and solve the challenges in sequence; each one builds on the last, and every step still earns its own verified proof.

Routing fundamentals

From your first static route to BGP policy at the edge, in the order the skills build.

10 challenges~7 h

Subnetting and addressing

Carve blocks to fit, size each subnet to its host count, and summarize routes without over-advertising.

4 challenges~2 h

Switching and VLANs

Trunks, access ports, inter-VLAN routing, spanning tree, and link bundling, the layer-2 core.

5 challenges~3 h

Virtualization and VM networking

Wire VMs into bridges and VLANs on a single host, and keep tenants isolated at layer 2.

3 challenges~110 min

OSPF in depth

Adjacencies, passive interfaces, path cost, and redistribution, then diagnose a stuck neighbor.

6 challenges~4 h

Edge services: NAT, DHCP, and time

Put a LAN online through one public IP, publish a service, relay DHCP across subnets, and lock down time.

5 challenges~3 h

Network security basics

Lock down hosts, write real ACL policy, and finish by catching attacks in logs.

9 challenges~6 h

Cloud and IaC security

Least-privilege security groups, Kubernetes NetworkPolicy and pod security, and safer Terraform.

5 challenges~3 h

Linux host administration

Users and permissions, least-privilege sudo, defusing a SUID bug, log rotation, and service hardening.

8 challenges~3 h

Road to DevOps

From running one service properly to CI, containers, Kubernetes, and Terraform.

10 challenges~4 h

Automation and templating

Render device configs from data, then drive a multi-router OSPF rollout from one idempotent playbook.

4 challenges~4 h

Troubleshooting drills

Nine broken networks. Diagnose from symptoms to root cause, ending with a full outage.

9 challenges~8 h