Learn

Learning tracks

Each track runs beginner → intermediate → advanced, with lessons, puzzles and labs along the way.

Linux

Beginner → Advanced

From first commands to kernel-depth troubleshooting.

PermissionssystemdjournalctlDisk & inodes
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Windows Server

Beginner → Advanced

AD, Group Policy, Event Viewer and PowerShell, demystified.

Active DirectoryKerberosNTFS ACLsGPO
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Networking

Beginner → Advanced

Packets to load balancers — and how to debug the path.

TCP/IPSubnettingHTTPLoad balancing
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DNS

Beginner → Advanced

The first domino in most outages. Master it.

ResolversRecord typesTTL & cachingSplit-horizon
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Storage

Beginner → Advanced

Disks to disaster recovery, RPO/RTO and restore testing.

RAIDLVMSnapshotsBackups
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Virtualisation

Intermediate → Advanced

Hypervisors, vCPUs, overcommit and live migration.

HypervisorsvCPU schedulingMemory overcommitSnapshots
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OpenStack

Intermediate → Advanced

Run a private cloud — Nova, Neutron, Cinder, Keystone, Glance.

KeystoneNovaNeutronCinder
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SRE

Intermediate → Advanced

SLOs, error budgets, golden signals and incident response.

SLI/SLO/SLAError budgetsGolden signalsIncident response
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PowerShell

Beginner → Advanced

Objects, not text — the pipeline that runs Windows.

Object pipelineWhere/Select/ForEachRemotingError handling
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Bash

Beginner → Advanced

Glue the system together — without the footguns.

Pipes & redirectionQuotingExit codesDefensive scripting
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Python for Sysadmins

Beginner → Advanced

When Bash isn't enough — automation that scales.

subprocessAPIsIdempotencyRetries & backoff
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Interview Prep

All levels

High-signal infra fundamentals, asked the way they ask them.

DNSPermissionsTroubleshooting judgementNetworking
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