What is the difference between a hard link and a symbolic link?
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01
Core Competency
Assesses fundamental understanding of Linux Administration conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
Both point to files, but at different levels.
- Hard link: another directory entry for the same inode. The file data is shared, and the link count increases. Deleting one name does not remove the data until all links are gone. Hard links cannot cross filesystems and usually cannot point to directories.
- Symbolic (soft) link: a separate file containing the path to the target. It can cross filesystems, point to directories, and become dangling if the target is removed. Permissions on the link itself are ignored; the target's permissions apply.
ln file.txt hard.txt # hard link
ln -s /var/www site # symbolic link
ls -li # shows inode and link count
readlink site
Use hard links for deduplication and backups within a filesystem, such as rsync --link-dest, and symlinks for flexible references such as versioned releases and config pointers.
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