CompTIA Exam Prep - ITF+, A+, Network+, Security+, CySA+

NTFS is the default file system for Windows and the only one that supports its security features. The A+ exam tests it on three fronts: how it compares with FAT32 and exFAT, how permissions work, and the security features that depend on it. NTFS, FAT32 and exFAT Feature NTFS FAT32 exFAT Max file size 16 TB+ 4 GB 16 EB Max volume size 256 TB+ 32 GB (Windows format) 128 PB Permissions Yes No No Encryption (EFS) Yes No No Journaling Yes No No Compression Yes No No macOS support Read only Read/write Read/write Two exam answers fall out of this table. The 4 GB FAT32 file size limit is why a large video will not copy to a FAT32 drive. And exFAT is the answer for cross-platform external drives with large files, because macOS can write to it while NTFS is read-only on macOS without third-party software. NTFS permissions versus share permissions The most testable part of NTFS, and the source of endless real-world confusion. NTFS permissions apply whether the file is accessed l...

APFS is the default file system on macOS, iOS, iPadOS and watchOS. For the A+ exam it appears in two places: knowing which file system belongs to which operating system, and knowing what APFS does that its predecessor did not. Why it replaced HFS+ HFS+ dates from 1998, when storage meant spinning platters and a few gigabytes. It was extended repeatedly but its assumptions were wrong for flash storage: it had no native snapshots, weak crash protection, and second-granularity timestamps. APFS arrived in 2017 designed for SSDs from the start. Feature HFS+ APFS Designed for Hard drives Flash and SSD Snapshots No Yes Copy-on-write No Yes Space sharing Fixed partitions Containers share free space Encryption Bolt-on (FileVault) Native, multi-key Timestamps 1 second 1 nanosecond Containers and volumes The structural change most worth understanding. On HFS+ you partitioned a disk and each partition had a fixed size; running one out of space while another sat half empty meant repart...

ext4 is the default file system on most Linux distributions, and ext3 is its predecessor. The exams test what journaling gives you, what ext4 added, and how these compare with the other file systems you will meet. Journaling The feature that defines both, and the reason ext2 is obsolete. A journaling file system records its intended changes in a journal before making them. After a crash the system replays or discards the journal rather than scanning the entire file system for inconsistencies. On ext2, an unclean shutdown meant an fsck that could take hours on a large volume. On ext3 and ext4 it takes seconds. ext3 offers three journaling modes, and they come up as a comparison. Mode What is journaled Trade-off journal Metadata and data Safest, slowest ordered (default) Metadata, with data written first Good balance writeback Metadata only Fastest, may expose stale data after a crash Ordered is the default because it prevents the worst outcome — metadata saying a file is writ...

FAT32 is the file system that refuses to die. Microsoft introduced it in 1996 with Windows 95 OSR2, replaced it with NTFS years ago, and it is still the default on USB sticks, SD cards, and camera storage worldwide — because it is the one format that everything can read. FAT32's limitations are severe and its compatibility is universal. Those two facts explain every decision anyone makes about it. The Limits You Must Know These are the most tested facts on the topic, and they are worth memorizing exactly. Maximum file size: 4 GB — strictly, 4 GB minus 1 byte. This is the one that bites people in practice, because a single video file, disk image, or large backup exceeds it and the copy fails partway through. Maximum volume size: 2 TB with standard 512-byte sectors. Windows will only format up to 32 GB through its own GUI, though it will happily read and use larger FAT32 volumes formatted elsewhere. That 32 GB figure is a Microsoft restriction, not a FAT32 one — a disti...