Linux File System
The Linux file system organizes and manages files in a hierarchical structure. Mastery of the Linux file system is essential for system administration, application deployment, and troubleshooting. This guide outlines the key concepts, structure, and common directories within the Linux file system.
Overview of the Linux File System
The Linux file system is structured as a tree, starting at the root directory (/) and branching into various subdirectories. Each directory can contain files, other directories, or both, forming a nested structure. Unlike Windows, Linux uses a single directory tree without drive letters.
The Root Directory (/)
The root directory (/) is the top level of the hierarchy. All files and directories on a Linux system are located under this root. Key subdirectories include:
/bin: Contains essential command binaries required for the system to function, such asls,cp, andmv./boot: Contains files necessary for booting the system, including the kernel and bootloader configurations./dev: Contains device files representing hardware components like hard drives and printers./etc: Stores system-wide configuration files and shell scripts used for administration tasks./home: Contains user home directories where personal files and directories are stored./lib: Holds essential shared libraries needed by the binaries in/binand/sbin./media: Mount point for removable media such as USB drives, CDs, and DVDs./mnt: Temporary mount point for filesystems./opt: Used for installing optional software packages./proc: A virtual filesystem providing information about running processes and the system./root: The home directory for the root user (system administrator)./sbin: Contains essential system binaries typically used by the root user for system administration./srv: Contains data for services provided by the system, such as web servers./tmp: A directory for storing temporary files./usr: Contains user utilities and applications. It's often the largest directory on a Linux system./var: Stores variable data like logs, databases, and email queues.
Key Concepts in the Linux File System
Hierarchical Structure
The Linux file system's hierarchical structure enables organized management of files and directories. This structure allows for efficient file location and management, whether dealing with configuration files, user data, or system resources.
Mount Points
In Linux, filesystems from different storage devices are "mounted" at specific directories, known as mount points. This allows access to the contents of these devices as part of the main filesystem. For example, a second hard drive might be mounted at /mnt/extra_storage.
File Permissions
Linux file permissions control who can read, write, or execute a file. Each file and directory has an associated owner, group, and set of permissions, which can be modified using commands like chmod, chown, and chgrp. Proper management of file permissions is critical for maintaining system security and ensuring correct application operation.
Navigating the Linux File System
Working with the Linux file system typically involves using the command line. Key commands include:
pwd: Displays the current working directory.cd: Changes the current directory.ls: Lists the contents of a directory.cp: Copies files and directories.mv: Moves or renames files and directories.rm: Removes files or directories.mkdir: Creates a new directory.rmdir: Removes an empty directory.
Learn more about Linux filesystem commands.