CompTIA A+ Core 2 (220-1202)Operating SystemsHard
A technician is preparing a bootable USB drive to install a custom Linux distribution on multiple identical systems. The distribution image needs to be copied to the USB drive in a way that makes it bootable and preserves the exact disk image structure, including partitions and bootloader. Which command-line utility in Linux is best suited for this task?
- Add
- Btar
- Cmv
- Dcp
Show answer & explanationAnswer & explanation
Correct answer: A. dd
The 'dd' command (disk duplicator) is a powerful low-level utility in Linux used for converting and copying files, often block-by-block. It is ideal for creating bootable USB drives from disk images (like .iso or .img files) because it copies the image directly to the raw device, preserving partition tables, boot sectors, and file system structures exactly as they are in the source image.
Why the other options are wrong
- B. tar (tape archiver) is used for archiving and compressing files and directories, not for writing raw disk images to a device.
- C. mv (move) moves or renames files and directories; it's not for creating bootable disk images.
- D. cp (copy) copies files and directories but does not copy an entire disk image block-by-block to a raw device in a way that makes it bootable.
dd command (disk duplicator)
A low-level, powerful command-line utility in Unix-like operating systems used for converting and copying files, often block-by-block, making it ideal for creating bootable media or backing up entire disks.
- Performs a raw, bit-for-bit copy of data.
- Used for creating bootable USB drives from .iso or .img files.
- Can be used for disk imaging, cloning, and wiping drives.
- Extremely powerful and can cause data loss if used incorrectly (e.g., specifying the wrong output device).
Memory trick: DD: 'Disk Duplicator' for 'Direct' copies!