Parts of a UFS File System

When you create a UFS file system, the disk slice is divided into cylinder groups, which are made up of one or more consecutive disk cylinders. The cylinder groups are then further divided into addressable blocks to control and organize the structure of the files within the cylinder group. Each type of block has a specific function in the file system.

A UFS file system has these four types of blocks:

• Boot block - Stores information used when booting the system

• Superblock - Stores much of the information about the file system

• Inode - Stores all information about a file except its name

• Storage or data block - Stores data for each file

See "The Structure of UFS File System Cylinder Groups" for more detailed information about each type of block.

If you want to customize a file system using arguments with the newfs command or the mkfs command, see Chapter 32, File System Reference for information about altering these parameters.