Operations, Security, and Recovery

Use Event Viewer, Get-WinEvent, and journalctl to narrow system problems by time, severity, service, and recent activity.

Explain the major boot stages on Windows and Linux and use a few practical tools to investigate slow or unhealthy startup behavior.

Explain a safe update workflow for Windows and Linux, apply updates deliberately, and verify whether a reboot is still required afterward.

Distinguish file backups, snapshots, and full-system recovery plans, and understand which recovery method fits which failure.

Use a structured troubleshooting flow so you can define the problem clearly, gather evidence, test carefully, and verify the fix.

Inspect, start, stop, restart, and enable services on Windows and Linux while using logs and status output to verify the result.

Use UFW to inspect firewall state, allow required access, and apply simple rules without locking yourself out.

Inspect iptables rules, understand chain order, and practice one small temporary rule change with a clear rollback.

Generate an SSH key pair, authorize the public key, and verify key-based login before changing server authentication settings.

Use chattr and lsattr on disposable files so you understand immutable and append-only attributes without risking important data.

See boot as a staged timeline so startup, services, login, and failure points become easier to reason about.

Use this when a service fails to start, immediately stops, or restarts into failure.