whatis inode
Inode
Also known as: index node
The on-disk record that stores a file's metadata (owner, permissions, size, timestamps, block locations), everything except its name.
What Is an Inode in Linux?
A file name is just a directory entry pointing at an inode number. The inode holds the real metadata and the map to the file's data blocks. ls -i shows inode numbers and stat shows the full record.
Filesystems like ext4 create a fixed number of inodes at format time, so a disk can report "no space left" while df -h shows free space, because millions of tiny files used every inode. df -i reveals it.
Example
stat /etc/hostname
df -iLearn more about Inode
- Inodes, Dentries and the Page Cache: What Happens When You Open a File A path is not a file. Resolving one walks a cache of directory entries to find an inode, which points at data the kernel keeps in the page cache. Understanding those three explains disk full errors with free space, and why the second read is instant.
- stat Command Explained stat shows detailed metadata about a file, far beyond what ls -l provides. This guide covers reading stat output, understanding inode numbers, and the three different timestamps every file has.
- Symlinks vs Hard Links Explained: The ln Command and How Links Actually Work Symbolic links point to a path; hard links point to the data itself. Understanding the difference explains why one survives renames, why the other breaks, and what ln -s actually creates.