Getting to know Red Hat Linux is much easier if you know the basic structure of the operating system. This chapter provides you with an overview of the directories that make up the Red Hat Linux file/directory structure, a brief overview of the FHS standard to which the Red Hat Linux structure adheres, and an introduction to the concept of virtual files and the related /proc directory.
Following is a list of the primary Red Hat Linux system directories. Each directory is described briefly. For additional directory information, refer to the Official Red Hat Linux Administrator’s Guide (Red Hat Press/Wiley, 2003).
/bin — Used to store user commands. The directory /usr/bin also stores user commands.
/sbin — Location of many system commands, such as shutdown. The directory /usr/sbin also contains many system commands.
/root — The home directory of root, the superuser.
/mnt — This directory typically contains the mount points for file systems mounted after the system is booted. For example, the default CD-ROM mount point is /mnt/cdrom.
/boot — Contains the kernel and other files used during system startup.
/lost+found — Used by fsck to place orphaned files (files without names).
/lib — Contains many library files used by programs in /bin and /sbin. The directory /usr/lib contains more library files.
/dev — Stores device files.
/etc — Contains many configuration files and directories.
/var — For "variable" files, such as log files and the printer spool.
/usr — Contains files and directories directly relating to users of the system.
/proc — A virtual file system (meaning a file system that’s not actually stored on the disk) that contains system information used by certain programs.
/initrd — A directory that is used to mount the initrd.img image file and load necessary device modules during bootup.
Do not delete this directory. You will be unable to boot your computer if you delete it and reboot your Red Hat Linux machine.
/tmp — A "scratch pad" for users and programs. /tmp has global read/write access.
/home — Typical location of user home directories.