macOS and Linux for A+ Core 2: Commands, Files, and Features

What Core 2 asks about Linux and macOS

Three 220-1202 objectives cover non-Windows systems. Objective 1.9 identifies Linux client features and tools. Objective 1.8 explains macOS features and tools. Objective 1.1 lists the operating system types and filesystems you need to recognize. None of them expects you to administer a server. The level is a support tech who can find a file, check a disk, install a package, and read a configuration file without panicking.

Linux commands by task, next to the Windows tool you know

All 27 commands below are on the 1.9 list. The Windows column is there to anchor the idea. Entries marked "not on the A+ list" are real Windows commands that 220-1202 does not name.

The Windows half of this table is covered in the Windows command line guide.

chmod in two minutes

Linux permissions are read (4), write (2), and execute (1) for three classes: the owner, the group, and everyone else. Add the numbers for each class.

• chmod 640 payroll.csv gives the owner read and write (6), the group read (4), and others nothing (0).
• chmod 755 cleanup.sh gives the owner everything (7) and everyone else read and execute (5).
• chmod u+x cleanup.sh adds execute for the owner without touching anything else.

A script that will not run with "Permission denied" usually needs the execute bit, which ties into the scripting guide.

sudo vs su

sudo runs a single command with elevated rights, and you return to your normal account when it finishes. su opens a shell as another account, root by default, and you stay in it until you exit. The root account has full control of the system. The passwd(5) manual notes that the superuser has user ID 0. Day-to-day work belongs in a normal account, with sudo for the few commands that need it.

Five configuration files and what each one controls

The last row is the Linux version of a classic Core 1 networking clue: if IP works and names do not, check DNS.

OS components. systemd starts and manages services after boot. The kernel talks to the hardware. The bootloader loads the kernel. A support tech mostly meets systemd when restarting a service.

Filesystems from objective 1.1

macOS features mapped to the job they do

Installing and removing apps. A .dmg is a disk image you open, usually to drag an app into /Applications. A .pkg is an installer package that runs an installer. An .app is the application bundle itself. The App Store is the managed route, and Apple ID plus corporate restrictions decide what a user may install. Most apps uninstall by moving them from /Applications to the Trash, though some ship their own uninstaller.

System folders. /Applications holds apps for all users, /Users holds home folders, /Library and /System hold system-wide resources, and each user has a Library folder inside their home folder.

The names have changed since the objectives were written. The 220-1202 objectives say "System Preferences." Apple renamed it System Settings in macOS Ventura (13). Apple's own FileVault instructions show the change: the macOS Monterey (12) page says "System Preferences," and the Ventura page says "System Settings." The objectives also list Rapid Security Response. Apple's current support pages use the name Background Security Improvements for security protections delivered between software updates, supported from macOS 26.1. Know the exam's terms and the names you will see on a current Mac.

Practice in a VM and on a Mac

Install a Linux distribution in a virtual machine and run every command in the first table at least once. Use man before searching the web. On a Mac, or with a friend's Mac, find each feature in the last table. When the commands feel automatic, practice A+ Core 2 Linux and macOS questions with Passy →.