CS AO study plan

Map the Linux boot sequence from firmware through init/systemd to the login prompt, and explain what each stage hands to the next

Practise the core command set for files, text, and processes (ls, find, grep, sed, awk, ps, top, kill) until each is used without looking up flags

Describe how systemd units, targets, and dependencies control service startup, and enable or disable a service deliberately

Read and interpret the main system log locations and the journalctl query options used to filter by unit, priority, and time

Configure persistent hostname, timezone, and network settings through the correct config files or tooling, then verify after a reboot

Install packages with the distribution package manager and resolve a deliberate dependency conflict

Explain the difference between a package-managed config file and a locally edited one, and preserve local changes across an upgrade

Compile and install software from source into a non-default prefix, then remove it cleanly

Create, modify, lock, and expire local user accounts and groups, and read the resulting entries in passwd, shadow, and group

Configure password aging and complexity rules through PAM and login.defs, then test a rejected weak password

Set up and troubleshoot sudo privileges using a drop-in file rather than editing the main sudoers file

Explain how SSH key authentication works and configure key-based login for a non-root account with the password disabled

Create, format, mount, and unmount partitions on a spare disk, and make a mount persistent through fstab

Extend a logical volume with LVM and confirm the filesystem grows to use the new space

Diagnose a full filesystem by locating large files and inodes, and reclaim space without deleting live data

Set and audit permissions, ownership, and special bits (setgid, sticky) on a shared directory

Assign a static IPv4 address, gateway, and DNS resolver, then prove connectivity with ping, dig, and a route lookup

Explain the role of each layer in name resolution and fix a deliberately broken resolver configuration

Open and close ports through the host firewall and confirm the effect with a port scan from another host

Use ss and tcpdump to identify which process owns a listening port and capture a short handshake

Harden SSH by disabling root login and password auth, then verify the change does not lock out the admin account

Apply file permissions and umask settings that satisfy a stated least-privilege requirement, and justify each choice

Configure host-based access controls and explain how they complement the network firewall

Describe how to check for and apply security updates, and what a compliance audit would expect to see as evidence

Set up a scheduled backup of a chosen directory and verify a restore into a clean location

Write a monitoring check that alerts on disk usage and service availability, and trigger it deliberately

Interpret CPU, memory, and I/O figures from standard tools and distinguish a real bottleneck from a noisy metric

Document a recovery runbook covering the steps, the owner, and the verification test

Work through a structured troubleshooting method (symptom, hypothesis, test, fix, verify) on two unrelated faults

Revisit the weakest domain from earlier weeks and close the specific gaps identified in practice

Take a timed mixed-domain practice set and review every wrong answer to its root cause

Write the operational procedure you would hand to a junior admin for a routine task such as adding a user or extending a volume