System Administration & IT Infrastructure Course

Lesson 1 • The Sysadmin Role and Mindset

Defines the scope of system administration across enterprise and SMB contexts. Establishes professional expectations that frame every subsequent chapter.

Lesson 2 • Linux Command-Line Essentials

Covers filesystem navigation, file manipulation, and process management in Linux. Provides the CLI fluency required for all server-side tasks ahead.

Lesson 3 • Hardware and Virtualization Concepts

Explains physical server components, RAID levels, and hypervisor types. Grounds students in the hardware layer before moving to software-defined infrastructure.

Lesson 4 • IT Infrastructure Service Models

Compares on-premises, colocation, and cloud delivery models for IT services. Sets strategic context for architectural decisions covered in later chapters.

Lesson 1 • Switching, Routing, and VLANs

Explains Layer 2 switching, Layer 3 routing, and VLAN segmentation for network isolation. Prepares students to collaborate with network teams on infrastructure design.

Lesson 2 • Firewall and Network Access Control

Introduces stateful firewalls, ACLs, and network segmentation strategies. Connects network security to the broader security posture built in later chapters.

Lesson 3 • Network Troubleshooting Methodology

Applies a structured OSI-layer approach to diagnosing connectivity failures. Students practice with ping, traceroute, tcpdump, and Wireshark captures.

Lesson 4 • Core Network Protocols and Services

Covers DNS, DHCP, NTP, and HTTP/S as foundational services every sysadmin manages. Students trace request flows to understand service dependencies.

Lesson 1 • RAID and Redundant Storage

Explains software and hardware RAID implementation, monitoring, and recovery. Prepares students to maintain data availability during disk failures.

Lesson 2 • Backup Strategies and Recovery Testing

Defines full, incremental, and differential backup strategies with retention policies. Students execute and verify restores to validate backup integrity.

Lesson 3 • Network-Attached and SAN Storage

Introduces NFS, SMB/CIFS, iSCSI, and Fibre Channel as shared storage protocols. Students configure NFS exports and iSCSI targets for multi-host access.

Lesson 4 • Logical Volume Management

Teaches LVM concepts including physical volumes, volume groups, and logical volumes. Enables flexible, non-disruptive storage resizing in production Linux systems.

Lesson 1 • Local User and Group Administration

Covers user account creation, password policies, and group membership on Linux and Windows. Builds the access control foundation extended by directory services later.

Lesson 2 • Role-Based Access Control Design

Teaches RBAC principles, permission inheritance, and access review processes. Connects identity governance to compliance requirements discussed in supplementary chapters.

Lesson 3 • Authentication Protocols and Standards

Covers Kerberos, NTLM, RADIUS, and SAML as enterprise authentication mechanisms. Students trace authentication flows to diagnose login failures.

Lesson 4 • Active Directory and LDAP Services

Explains AD domain structure, organisational units, and LDAP directory queries. Students join Linux hosts to an AD domain and manage objects via CLI and GUI.

Lesson 1 • Infrastructure as Code Principles

Introduces IaC concepts, idempotency, and declarative vs. imperative approaches. Establishes the philosophy behind all configuration management tools covered next.

Lesson 2 • Configuration Management with Ansible

Teaches Ansible inventory, playbooks, roles, and variable management for Linux and Windows. Students automate multi-host configuration tasks with reusable role structures.

Lesson 3 • Operating System Installation and Kickstart

Covers manual and automated OS installation using PXE boot and kickstart files. Automation here eliminates manual errors and accelerates server provisioning.

Lesson 4 • Secrets and Credential Management

Introduces secrets vaults, environment variable injection, and credential rotation workflows. Secure secret handling is essential before deploying automated pipelines.

Lesson 1 • Alerting Design and On-Call Workflows

Covers alert threshold design, severity classification, and on-call rotation tooling. Well-designed alerts reduce noise and accelerate mean time to resolution.

Lesson 2 • Centralised Log Management

Teaches syslog, journald, and log shipping to a centralised aggregation platform. Centralised logs enable cross-host correlation required for incident investigation.

Lesson 3 • Prometheus and Grafana Stack

Covers Prometheus scraping, PromQL queries, and Grafana dashboard construction. Students build a working monitoring stack for a multi-server lab environment.

Lesson 4 • Monitoring Fundamentals and Metrics

Defines the four golden signals and key infrastructure metrics for CPU, memory, disk, and network. Metric selection here drives the alerting strategy built throughout the chapter.

Lesson 1 • Security Baseline and Hardening Standards

Introduces CIS Benchmarks and STIG-style hardening checklists for OS configuration. Baseline standards provide the measurable security target for all hardening tasks.

Lesson 2 • Audit Logging and Compliance Evidence

Configures auditd rules to capture privileged actions and generate compliance evidence. Audit trails support both internal reviews and external regulatory assessments.

Lesson 3 • Host-Based Security Controls

Covers SELinux, AppArmor, host-based firewalls, and file integrity monitoring tools. These controls limit blast radius when perimeter defences are bypassed.

Lesson 4 • Vulnerability Scanning and Remediation

Covers authenticated vulnerability scanning, CVSS scoring, and remediation prioritisation. Students run scans, triage findings, and apply fixes in a lab environment.

Lesson 1 • High Availability Architecture Principles

Defines availability tiers, single points of failure, and redundancy patterns for infrastructure. HA design principles guide every architectural decision in this chapter.

Lesson 2 • Failover Testing and Runbook Execution

Covers planned failover procedures, chaos testing principles, and runbook validation. Regular failover drills expose gaps before real incidents occur.

Lesson 3 • Load Balancing and Service Redundancy

Covers Layer 4 and Layer 7 load balancing, health checks, and session persistence. Students configure HAProxy or Nginx to distribute traffic across redundant backends.

Lesson 4 • Database and Storage Replication

Explains synchronous and asynchronous replication for databases and block storage. Replication strategy directly determines achievable recovery point objectives.