Creating Links: Hard Links & Symlinks

A link lets more than one name point to file data. Linux supports two kinds: hard links and symbolic (soft) links.

On disk, a file is an inode holding the data and metadata. A filename is just a directory entry pointing to an inode. This is the key to understanding links.

A hard link is another directory entry pointing to the same inode. Use ln with no flags.

Because both names point to one inode, editing through either changes the same data. The file is only deleted when the last link is removed.

Hard links cannot cross filesystems and usually cannot link directories. They also cannot point to a file on another disk or partition.

A symlink is a small file that stores a path to another file. Create it with ln -s.

A symlink points to a name, not an inode. If the target is deleted or moved, the symlink becomes a broken (dangling) link.

Unlike hard links, symlinks can cross filesystems and can point to directories — which is why they are used for things like rotating release folders.

ls -l shows symlinks with an arrow and an l file type. For hard links, the link count column shows how many names share the inode.

Use rm on a symlink to delete the link, not the target. Take care: a trailing slash on a symlink-to-directory can behave unexpectedly.

Use a symlink for shortcuts, cross-filesystem references, and directories (most common). Use a hard link when you need multiple equal names to identical data on the same filesystem.

Test your understanding.

You learned about links: hard links add a name to the same inode (same filesystem, no directories, data survives until the last link is gone), while symlinks (ln -s) store a path, can cross filesystems and point to directories, but can break.