Hard Link vs Soft Link in Linux: Key Differences and Usage

In Linux, a hard link is a direct pointer to the file's data on disk, sharing the same inode, while a soft link (or symbolic link) is a shortcut that points to the file name and can cross file systems. Hard links cannot link directories or files on different partitions, but soft links can.

Quick Comparison

Here is a quick side-by-side comparison of hard links and soft links in Linux.

Feature	Hard Link	Soft Link (Symbolic Link)
Points to	Same inode (file data) directly	File name/path (reference)
Can link directories?	No	Yes
Can cross file systems?	No	Yes
Effect if original file is deleted	File data remains accessible	Link becomes broken (dangling)
Identified by	Same inode number as original	Different inode, shows as link
Creation command	ln source target	ln -s source target

Key Differences

A hard link creates another directory entry for the same file data by pointing to the same inode number. This means both the original file and the hard link are indistinguishable; deleting one does not remove the actual data until all hard links are deleted. However, hard links cannot be created for directories to avoid filesystem loops, and they cannot span across different mounted file systems.

On the other hand, a soft link or symbolic link is a special file that contains a path to another file or directory. It acts like a shortcut. If the original file is moved or deleted, the soft link becomes broken and points to a non-existent location. Soft links can link directories and can cross file system boundaries, making them more flexible but less robust than hard links.

In summary, hard links are more like clones of the file entry sharing the same data, while soft links are pointers or shortcuts to the file name.

Code Comparison

Creating a hard link to a file named file.txt:

bash

ln file.txt hardlink.txt
ls -li file.txt hardlink.txt

Output

123456 -rw-r--r-- 2 user user 20 Jun 10 10:00 file.txt
123456 -rw-r--r-- 2 user user 20 Jun 10 10:00 hardlink.txt

Soft Link Equivalent

Creating a soft (symbolic) link to the same file file.txt:

bash

ln -s file.txt softlink.txt
ls -li file.txt softlink.txt

Output

123456 -rw-r--r-- 1 user user 20 Jun 10 10:00 file.txt
234567 lrwxrwxrwx 1 user user 8 Jun 10 10:01 softlink.txt -> file.txt

When to Use Which

Choose a hard link when you want multiple directory entries to the exact same file data that remain valid even if one link is deleted, and when you are working within the same file system and not linking directories.

Choose a soft link when you need to link directories, link files across different file systems, or want a flexible shortcut that can point to files or directories by name, understanding that if the original is removed, the link breaks.

Key Takeaways

Hard links point directly to file data and share the same inode number.

Soft links are shortcuts pointing to file names and can cross file systems.

Hard links cannot link directories; soft links can.

Deleting the original file breaks soft links but not hard links.

Use hard links for robust same-filesystem duplicates, soft links for flexible shortcuts.