Linux and the role of each directory's contents
1) the root directory "/"
Located in the root directory of the top-level directory structure, using a slash (/) that is similar to the Windows operating system "C: \", contains the Fedora operating system, all the directories and files.
2) / bin
Directory, also known as binary directory that contains the binary image of those important linux commands for system administrators and ordinary users. The directory is stored in a variety of content including executable files, and some executable symbol connection. Commonly used commands are: cp, dmesg, kill, login, rm, ping, chomd, bash, cat, echo, ls, mail, vi and so on.
3) / boot
Directory and file storage system core files must be read at startup, including the Linux kernel binary image.
4) / dev
Directory holds the external device code files, which are special, in fact, they all point to the representative of peripherals, such as terminals, disk drives, optical drives, printers, and so on. You can access these external devices, and access a file or a directory is no different. As subdirectories under the / dev / cdrom represents CD-ROM directory; subdirectory of / dev / console indicate that the console; subdirectory of / dev / fd represents floppy; subdirectory of / dev / hd represents a partition on the hard disk; lp0 indicates the printer ; ttyS0 represents the system serial device; dsp representation system speaker equipment. For example, type "cd / dev / cdrom" in the system, you can see the drive in the file; type "cd / dev / mouse" to see the relevant documents of the mouse.
/ Cdrom directory when the newly installed system is empty, you can hang on the CD-ROM file system under the directory, such as "mount / dev / cdrom / cdrom".
5) / etc
Directory is the center of the entire Linux system, which contains all system management and maintenance of the configuration files, such as dhcpd.conf, host.conf, logrotate.conf, man.config, mke2fs.conf, modprobe.conf, resolv.conf, sysctl .conf, syslog.conf (or rsyslog.conf), xinetd.conf yum.conf and the like, other configuration files are located in a separate subdirectory. It should be noted that normally the backup directory of important configuration files, so need to be able to quickly restore the system. Used to store system configuration files and related files specific host. For example, records the user account password file name, the projection of shadow password files. The directory does not contain any binary files, and all files in that directory is used mainly by administrators, ordinary users only have to read their rights. The directory also contains some network configuration files, file systems, x system configuration files, device configuration information, user information and other settings.
Cron process scheduling is used to store configuration and control files to run background processes used. Other directories include / etc / four directories cron.hourly, cron.daily, cron.weekly and cron.monthly etc. crontab file definition.
/ Etc / cups for a variety of configuration files stored in Common UNIX Printing System (Commom UNIX Printing System, CUPS) uses.
/ Etc / default file which is used to provide part of the tools (such as useradd program) to use variables and their default values.
/ Etc / httpd
Apache configuration root directory files. Apache is a versatile, high-performance HTTP server, is the world's most popular Web server. Apache modular design approach to support dynamic run-time module selection, web hosting, and service number of dynamic adjustment process.
Required by the init script file /etc/init.d scheduled for execution for storing time to enter the corresponding run level. In Fedora
Linux system, this is just a symbolic link file, the actual directory should be /etc/rc.d/init.d.
/etc/ipsec.d IPSee used for storing configuration files.
/ Etc / kde which contains part of the KDE KDM configuration files and initialization files.
/ Etc / pki for storing various keys, such as keys used to install packages and the like.
/ Etc / ppp PPP for storing scripts and configuration files.
/etc/profile.d for storing / etc / profile and other auxiliary initialization files, such as lang.sh script files.
/etc/rc.d for storing into the corresponding run level init process is scheduled for execution by the script file. Containing init.d and rcN.d etc subdirectory (where N is 4, 5 and 6, indicating the system run level).
Root directory / etc / samba Samba configuration file. Samba is a general term for network sharing software, Linux systems to achieve the SMB protocol that allows Linux systems to Windows system file and print sharing services.
/ Etc / security file basic safety control user storage, including registration control files, control file access control, and resource limit control files.
/ Etc / selinux SElinux (Security Enhanced Linux, by the US National Security (National Security Agency) GPL project leader development, it has a flexible mandatory access control architecture, designed to improve the security of Linux systems, providing robust security assurances, protects against unknown attacks, allegedly equivalent to the B1 level of military security. than MS
NT called C2 Contour much. After applying SELinux, you can mitigate malicious attacks or malware bring disaster, and provide confidentiality and integrity of information security a high high demands. ) Root directory of the configuration file.
/ Etc / skel stored therein a default initialization files, such as .bash_logout, .bash_profile, .bashrc, .emacs, .kde and .zshrc like. Whenever add a new user, the system will copy some of these initialization file to the user's home directory. Note: These files are hidden files. (Ie. "" Beginning of the file name)
/ Etc / ssh directory contains system configuration, and system boot process need to use the various configuration files, a variety of back-office services to maintain the configuration process is chkconfig root directory files. For example, the time zone in which the file that contains the system clock settings, keyboard file contains type definitions keyboard, init file contains parameters defined process used to guide the like.
/ Etc / tomcat5 tomcat root directory
/ Etc / vsftpd FTP server contains the configuration files, including important documents vsftpd.conf, ftpusers and user_list like.
/etc/xinetd.d xinetd service which includes all of the traditional process control network used by the service profile, in particular, contain telnet and other network applications configuration file. On Linux systems, the original inetd xinetd service by the more powerful process replaced the original inetd.conf configuration file may also be replaced by xinetd.d catalog a series of individual profiles.
/ Etc / yum yum software update tool which contains configuration files used.
/etc/yum.repos.d which contains configuration files for each depot.
6) / lib
Storage directory necessary runtime, mainly programming language library. A typical Linux operating system contains C, C ++ and Fortran libraries. These languages to develop applications that can use the programming language library file. This allows software developers to utilize those prewritten and tested functions. Library file contains the standard C library /lib/libc.so.*, math library libm.so. *, shared dynamic-link library / lib / ld / so and the directory / bin and / sbin used under other shared libraries . / Lib / modules directory of the storage system core modules, some of which may be part of a modular core body does not need to put in the system kernel compile time, to avoid too large and the body becomes less efficient.
7) / lost + found
The catalog and store all other directories have no associated file. System errors or problems occur, Fedora will automatically scan the disk drives, fix bugs, if missing or incorrect fragment found these fragments transforming into a file stored here, for further processing administrator.
8) / mnt
This directory is the default file system temporary mount point, which is a common installation point, you can temporarily install any file system or remote resources. System administrators perform mount
Command completes loading work. In the system, this directory contains a CD-ROM, floppy disk and mount point.
9) / proc
Proc process file system root directory, which is part of the file corresponding to a running process, can be used to access the current process's address space. It is a very special virtual file system, which does not contain the "real" file, but the system can be used to refer to information about the current operation of the system, such as CPU, memory, uptime, software configuration and hardware configuration information, which It is in memory, generated by the system itself.
/ Proc / net files which represent the status of various network protocols (such as TCP, UDP, and ARP, etc.) and statistics.
/ Proc / sys This directory is not only there are a variety of information systems, but also contains the system kernel and TCP / IP network tunable parameters. Wherein the kernel subdirectory containing the shared memory and message queue tunables, net subdirectory contains TCP / IP various tunable parameters. For example, shmmax file containing the definition of the largest shared memory system, if you use "echo somevalue>
/ Proc / sys / kernel / shmmax "command, you can directly modify kernel parameters to run the system without having to reboot the system. This approach to be careful, some files may contain multiple values, or a different type of value, therefore, modify previously we must understand the meaning and the actual value of the parameter. for every time you start the system can be used to customize the system tunable parameters can be set sysctl.conf configuration file, or write your own Shell startup script.
10) / opt
Directory is used to install additional packages, the user invoking the program package placed in the directory / opt / package_name / bin, package_name is the name of the installation package.
11) / root
Superuser root's home directory (in Linux systems, the slash character "/" is the root of the entire system, rather than the super-user's home directory.)
12) / sbin
Directory / sbin, / usr / sbin and / usr / local / sbin directory to store the program that need to perform to start the system, such as management tools, applications and generic root user privileges command and so on. Such as those containing getty, init, update