CompTIA’s A+ Certification exam: Core 2 (220-1202)

Which Linux command is used to print the full contents of a file to the screen at once?

cat

Which of the following commands is used on a Linux system to convert and copy files from one hard disk to another?

dd

The customer service manager at Dion Training is having issues with her Windows 10 laptop. A technician believes that the operating system may have been corrupted by a piece of malware. The technician has removed the malware and wants to perform an installation or upgrade that will recopy the system files and revert most of the system settings to their default configurations while still preserving the user’s personalization settings, data files, and any applications installed through the Windows store. The technician has been told that they may delete any applications installed by the user, though, since they may have been infected by the malware. Which of the following types of upgrades or installations should the technician use?

Refresh installation

Which of the following is required for evidence to be admissible in a court of law?

Chain of custody

Strongest Wi-Fi encryption standard and should be enabled for better wireless security

WPA3 encryption

Limits Wi-Fi signal range so neighbors cannot detect or connect to the network

Reduce transmission power

Hides the network name so nearby users cannot easily locate it

Disable SSID broadcast

Most important action before granting remote access to a server to prevent infection

Install latest security updates and patches

Document showing the physical layout of cables, ports, and hardware

Physical network diagram

Protocol that allows devices like game consoles or VoIP handsets to automatically configure firewall ports

UPnP

Key fob device generating time-synchronized one-time passwords for authentication

Hardware token

Recommended workaround for a cracked laptop screen when internal hardware keys prevent replacement

External 15" tablet/monitor

Best action when a customer needs immediate smartphone functionality after water damage

Offer replacement phone

Best method to prevent malware that spreads using stolen credentials

Anti-virus with heuristic analysis

Not required in a DHCP scope for clients to access the internet

Reservations

Windows tool used to import and manage x.509 digital certificates

Certificate manager

Command used to rebuild Boot Configuration Data when Windows installation is missing

bootrec /rebuildbcd

Reason an offsite backup facility cannot destroy old tapes during a forensic investigation

Legal hold

Best way to isolate an internet-accessible FTP server to protect the internal network

Screened subnet

Private IP addresses in the Class A range are from 10.0.0.0 to 10.255.255.255. They are not routable over the Internet and are used within local networks

10.5.34.15

The command used to repair a partition boot sector in Windows is bootrec /fixboot, which addresses “BOOTMGR is missing” errors during startup

bootrec /fixboot

A local text file mapping hostnames to IP addresses that can be modified by attackers to redirect traffic

Check the host.ini file

On an MBR-partitioned system, only four primary partitions are allowed

Primary

When an application requires more RAM than installed, the system uses part of the storage drive as virtual memory, which slows performance

If an application needs more RAM than is available, the system uses part of the storage drive as virtual memory

A command-line utility that shows current TCP connections, routing tables, and network statistics

netstat

A DHCP reservation works by linking a specific MAC address to a specific IP address within the DHCP scope

By matching a MAC address to an IP address within the DHCP scope

To repair the boot sector on a Windows 10 disk, the command bootrec /fixboot is used

bootrec /fixboot

A targeted email attack aimed at specific individuals to steal sensitive information

Spear phishing

A unique identifier assigned to each piece of hardware in an organization’s asset management system

Asset ID

The Linux command dd can overwrite an entire hard disk with zeros, useful for wiping data

dd

A Windows 10 power state that saves the current session to memory with minimal power usage

Sleep

On Linux, the yum command is used to install, remove, or update software packages

yum

Grandfather-father-son (GFS)

Backup rotation scheme using daily (son), weekly (father), and monthly (grandfather) backups.

3-2-1 backup rule

Maintain 3 copies of data, on 2 different media types, with 1 copy off-site.

Tower of Hanoi

Backup rotation scheme rotating media sets to minimize wear; uses exponential rotation.

FIFO Backup

Backup scheme using a set number of tapes, overwriting the oldest with the newest.

shutdown +11

Linux command to shut down the system in 11 minutes.

shutdown 11:00

Linux command to shut down the system at 11:00 AM.

shutdown now

Linux command to shut down the system immediately.

Insider threat

Threat from current/former employees or partners misusing authorized access.

Zero-day

Attack exploiting a software vulnerability that hasn't been patched yet.

Known threat

Threat identifiable by basic signature or pattern matching.

Advanced Persistent Threat (APT)

Attacker with ability to obtain and maintain long-term access using exploits and malware.

Task Manager

Windows tool to monitor processes, performance, and services; used to kill unresponsive tasks.

Processes Tab

Task Manager tab to view system resource utilization and troubleshoot applications.

Mobile App Troubleshooting

If an app is slow/buggy, uninstall it, reboot the device, and reinstall the app.

IoT Security Best Practices

Use WPA2 encryption and place devices in a DMZ/screened subnet.

Data Wiping

Overwriting disk data with software to destroy it while allowing hardware reuse.

Degaussing

Demagnetizing a hard drive to erase data; renders the drive unusable.

Purging

Removing sensitive data via internal electronics, degaussing, or cryptographic erase.

Shredding

Physical destruction of a hard drive preventing reuse.

Low-level formatting

Disk operation making data recovery impossible; allows drive reuse.

Standard formatting

High-level formatting that may allow data recovery.

Character data type

Stores a single character (e.g., 'A'); consumes 1 byte.

String data type

Stores a group of characters; consumes variable storage.

Boolean data type

Stores TRUE/FALSE; consumes 1 bit.

Integer data type

Stores whole numbers; usually consumes 8 bytes.

Repair installation

Replaces OS files with new copies of the same version; fixes boot issues without deleting user data.

Clean install

Installing OS on a new/formatted drive; deletes all user data and settings.

In-place upgrade

Installing newer OS on top of existing one; preserves apps, settings, and data.

Refresh installation

Reinstalls OS files and resets settings; preserves user data and Store apps but deletes others.

ip command

Linux command to display wired network connection info (IP, subnet, MAC).

nslookup

Command to display and troubleshoot DNS records.

netstat

Command to display network statistics like active TCP connections and ports.

ipconfig

Windows command to display TCP/IP network configuration.

chmod

Linux command to change file or directory permissions.

chown

Linux command to change the owner of a file or directory.

pwd

Linux command to display the present working directory path.

sudo

Linux command to execute programs as superuser (root).

Encrypting File System (EFS)

Windows NTFS feature to encrypt individual files/folders for user privacy.

BitLocker

Windows feature for full disk encryption of the internal drive.

BitLocker to Go

Windows feature for full disk encryption of external drives (USB).

FileVault

macOS full disk encryption program.

Incident Response Step 1

Identify the issue.

Troubleshooting Service Failure

Reboot into Safe Mode to check for driver/service conflicts.

APIPA

Windows feature assigning 169.254.x.x IP when DHCP fails.

Private IP Address Ranges

10.x.x.x, 172.16-31.x.x, 192.168.x.x.

MAC Allow List

Security measure allowing only specific MAC addresses to connect to the network.

Swap partition

Linux hard disk section used as virtual memory when RAM is full.

ext3

Linux journaled file system supporting up to 32 TB.

ext4

Modern Linux journaled file system supporting up to 1 EB.

NFS (Network File System)

Protocol to mount remote storage as local file system on Linux.

Port Security

Switch feature limiting the number of MAC addresses allowed on a port.

Firewall

Security system preventing unauthorized access from external networks.

Single Sign-On (SSO)

Authentication method allowing one set of credentials for multiple services.

Login Script

Script running at user login to configure the environment.

pathping

Windows tool identifying network latency/loss spots by pinging nodes over time.

ping

Tool to test host reachability on an IP network.

net use

Windows command to connect/configure shared network resources.

Invalid Credentials Loop

Likely caused by Multi-factor authentication (MFA) requirement despite correct password.

ls

Linux command to list the files or directories in the current path.

pwd

Linux command to display the present working directory (current directory) path to the terminal.

chkdsk

Windows command to check the file system and file system metadata of a volume for logical and physical errors.

System File Checker (SFC)

Windows utility to scan for and restore corrupted Windows system files from the command line.

CRT monitor

Older-style monitor containing large capacitors that retain high levels of electricity, presenting a large risk of electrical shock.

Printer Troubleshooting First Step

Check the status of the print server queue to determine if the print job has become stuck.

Biometric lock

Physical security feature using identifying features like facial or fingerprint patterns to authenticate a user.

Badge reader

Physical security feature that reads a security badge (using RFID, smart card, or barcode) to authenticate a user.

Cable locks

Security device used for laptops, not servers or server rooms.