System Administration Guide: Basic Administration


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The following table describes the default directories in the /usr file system.

Table 44-2 Default Directories in the /usr File System

Directory	Description
`4lib`	SunOS 4.1 binary compatibility package libraries
`5bin`	Symbolic link to the `/usr/bin` directory
`X`	Symbolic link to the `/usr/openwin` directory
`adm`	Symbolic link to the `/var/adm` directory
`apache`	Apache executables, loadable modules, and documentation
`aset`	Directory for Automated Security Enhancement Tools (ASET) programs and files
`bin`	Location for standard system commands
`ccs`	C compilation programs and libraries
`demo`	Demo programs and data
`dict`	Symbolic link to the `/usr/share/lib/dict` directory, which contains the dictionary file used by the UNIX spell program
`dt`	Directory or mount point for CDE software
`games`	An empty directory, which is a remnant of the SunOS 4.0-4.1 software
`include`	Header files for C programs, and so on.
`iplanet`	Directory server executables, loadable modules, and documentation
`j2se`	Java 2 SDK executables, loadable modules, and documentation
`java`*	Directories that contain Java programs and libraries
`kernel`	Additional kernel modules
`kvm`	Obsolete
`lib`	Various program libraries, architecture-dependent databases, and binaries not invoked directly by the user
`local`	Commands local to a site
`mail`	Symbolic link to the `/var/mail` directory
`man`	Symbolic link to the `/usr/share/man` directory
`net`	Directory for network listener services
`news`	Symbolic link to the `/var/news` directory
`oasys`	Files for the Form and Menu Language Interpreter (FMLI) execution environment
`old`	Programs that are being phased out
`openwin`	Directory or mount point for OpenWindows software
`perl5`	Perl 5 programs and documentation
`platform`	Supported platform files. For more information, see Table 44-3.
`preserve`	Symbolic link to the `/var/preserve` directory
`proc`	Directory for the `proc` tools
`pub`	Files for online man page and character processing
`sadm`	Various files and directories related to system administration
`sbin`	Executables for system administration
`sbin/install.d`	Custom JumpStart scripts and executables
`sbin/static`	Statically linked version of selected programs from `/usr/bin` and `/usr/sbin`
`sbin/sparcv7` and `sparcv9`	32-bit and 64-bit versions of commands on SPARC systems
`sbin/i86`	x86 architecture specific commands
`sfw`	GNU and open source executables, libraries, and documentation
`share`	Architecture-independent sharable files
`share/admserv5.1`	iPlanet Console and Administration Server 5.0 documentation
`share/audio`	Sample audio files
`share/ds5`	iPlanet Directory Server 5.1 Documentation
`share/lib`	Architecture-independent databases
`share/man`	Solaris manual pages
`share/src`	Source code for kernel, libraries, and utilities
`snadm`	Programs and libraries related to system and network administration
`spool`	Symbolic link to the `/var/spool` directory
`src`	Symbolic link to the `share/src` directory
`tmp`	Symbolic link to the `var/tmp` directory
`ucb`	Berkeley compatibility package binaries
`ucbinclude`	Berkeley compatibility package header files
`ucblib`	Berkeley compatibility package libraries
`vmsys`	Directory for Framed Access Command Environment (FACE) programs
`xpg4`	Directory for POSIX-compliant utilities

The Platform-Dependent Directories

The following table describes the platform-dependent objects in the /platform and /usr/platform directories.

Table 44-3 The /platform and /usr/platform Directories

Directory	Description
`/platform`	Contains a series of directories, one directory per supported platform that needs to reside in the root (`/`) file system.
`/platform/*/kernel`	Contains platform-dependent kernel components, including the file `unix`, the core kernel that is platform-dependent. For more information, see `kernel`(1M).
`/usr/platform`	Contains platform-dependent objects that do not need to reside in the root (`/`) file system.
`/usr/platform/*/lib`	Contains platform-dependent objects similar to those objects found in the `/usr/lib` directory.
`/usr/platform/*/sbin`	Contains platform-dependent objects similar to those objects found in the `/usr/sbin` directory.

The Structure of Cylinder Groups for UFS File Systems

When you create a UFS file system, the disk slice is divided into cylinder groups, which is 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:

Block Type	Type of Information Stored
Boot block	Information used when booting the system
Superblock	Detailed information about the file system
Inode	All information about a file
Storage or data block	Data for each file

The following sections provide additional information about the organization and function of these blocks.

The Boot Block

The boot block stores objects that are used in booting the system. If a file system is not to be used for booting, the boot block is left blank. The boot block appears only in the first cylinder group (cylinder group 0) and is the first 8 Kbytes in a slice.

The Superblock

The superblock stores much of the information about the file system, which includes the following:

Size and status of the file system
Label, which includes file system name and volume name
Size of the file system logical block
Date and time of the last update
Cylinder group size
Number of data blocks in a cylinder group
Summary data block
File system state
Path name of the last mount point

Because the superblock contains critical data, multiple superblocks are made when the file system is created.

A summary information block is kept within the superblock. The summary information block is not replicated, but is grouped with the primary superblock, usually in cylinder group 0. The summary block records changes that take place as the file system is used. In addition, the summary block lists the number of inodes, directories, fragments, and storage blocks within the file system.

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