CompTIA Linux+ Free Practice Test

Correct Answer: Define full path to binaries inside the script
Explanation:
Cron runs with minimal PATH. Scripts that rely on interactive shell paths fail unless absolute executable locations are given. Defining full paths resolves environment disparity.

Correct Answer: Verify UDP/TCP input modules and listener ports in rsyslog.conf
Explanation:
rsyslog does not accept network logs unless input modules are explicitly enabled (imudp/imtcp). Correct listener configuration is required for ingestion regardless of service state.

Correct Answer: Set context type httpd_cache_t on the target directory
Explanation:
Assigning an appropriate SELinux context grants NGINX controlled write rights without weakening global enforcement. This respects least-privilege and preserves mandatory access controls.

Correct Answer: Extend physical volume → extend logical volume → resize filesystem
Explanation:
Full hot-growth requires updating each abstraction layer. PV expansion informs LVM of new capacity, LV rescales, then filesystem grows to use the additional space live.

Correct Answer: Apply cgroup CPU quotas to PHP-FPM service
Explanation:
cgroups isolate compute utilization at service level. PHP can be throttled independently, preventing CPU starvation of MySQL or other critical daemons.

Correct Answer: Unmount the filesystem immediately
Explanation:
Unmounting prevents overwritten blocks. EXT4 journaling reuses freed space rapidly, and continued writes destroy recovery chances. Unmount preserves current block state for forensic tooling.

Correct Answer: Tune swappiness value lower
Explanation:
Reducing swappiness decreases kernel tendency to push pages into swap under memory pressure, maintaining performance for large-memory workloads and reducing stall time caused by swap page churn.

Correct Answer: Add nofail or x-systemd.device-timeout to the fstab entry
Explanation:
Systemd delays boot when waiting for mounts listed in fstab. Specifying nofail or timeout options prevents blocking, ensuring system boot even if storage appears late or requires initialization.

Correct Answer: Modify sshd_config to disable PasswordAuthentication and restart SSH
Explanation:
Disabling PasswordAuthentication ensures SSH accepts only public key-based authentication globally. This eliminates brute-force password vectors while maintaining secure authorized key access for all accounts.

Correct Answer: Replace SATA cable and controller port
Explanation:
Intermittent I/O errors with passing SMART often indicate a failing data path, not the disk itself. Faulty cables or controller lanes cause signal degradation that triggers read-only remounting for filesystem protection. Replacing the cable + port isolates the hardware layer, preventing recurring corruption and premature disk replacement.