/bin Essential command binaries Holds the files needed to bring the system up and run it when it first comes up in single-user mode. Holds system utilities

/boot Static files of the boot loader Contains all of the files needed to boot the system.

/dev Device files

/etc Machine–local system configuration files One of the most important is /etc/passwd

/etc/X11 Machine–local configuration files for the X Window System

/home User home directories

/lib Shared Libraries

/lib/modules Loadable kernel modules

/mnt Mount point for temporarily mounting filesystems

/opt Add-on software packages. (optional)

/proc Kernel and process information virtual filesystem

/root home directory for root

/sbin Essential system binaries Utilities used for system administration are stored in /sbin and /usr/sbin.

/sbin *also /sbin directory includes utilities needed during the booting process

/usr/sbin holds utilities used after the system is up and running

Older versions of linux In older versions of Linux, many system administration utilities were scattered through several directories that often included other system files (/etc, /usr/bin, /usr/adm, /usr/include).

/sys Device pseudofilesystem

/tmp temporary files

/usr Second major hierarchy. Traditionally includes subdirectories that contain information used by the system. Files in /usr subdirectories do not change often and may be shared by several systems.

/usr/bin Most user commands. Contains the standard linux utility programs. that is binaries that are not needed in single-user mode.

/usr/lib Libraries

/usr/local Local hierarch Holds locally important files and directories that are added to the system. can include bin, games, include, lib, sbin, share, and src

/var Variable data, files with contents that vary are stored here

/var/log Log files Contains lastlog (a record of the last login by each user), messages (system messages from rsyslogd), and wtmp (a record of all logins/logouts).

cd Associates you with another working directory

chmod Changes the access permissions on a file

getfacl Displays a files ACL

ln Makes a link to an existing file

mkdir Creates a directory

pwd displays the pathname of the working directory.

rmdir Deletes a directory.

setfacl Modifies a files ACL

ACL Access control lists.

ACL's allow you share selected files with other users.

Maximum file name 255 characters

Should you use spaces in filenames. No

stat Displays information about a file or filesystem.

T or F Linux is case sensitive true

T or F file name extensions are mandatory False they are not neccesary

Absolute pathname You can build the absolute pathname of a file by tracing a path from the root directory through all the intermediate directories to the file

relative pathname traces a path from the working directory to a file

The "." is synonymous with the pathname of the working directory and can be used in its place

The ".." is synonymous with the pathname of the parent of the working directory.

rmdir -r deletes directory and files inside.

touch creates an empty file

ls -l displays file permissions

chmod a all users

chmod u user/owner of the file

chmod g group

chmod 0 other

Link is a pointer to a file

ln creates a hard link

rm removes a link

R W X Read write execute

ls -l Long Listing

ls -i inode

ls -a show hidden files

ls -A show hidden files, wont show .. parent or .

ls -h human readable

ls -F shows a / if directory

ls -t time

ls -r reverse

ls -R recursive

ls -s sort by size

mount mount a filesystem

umount unmount a filesystem

df show amount of disk space free

du show amount of disk space used

stat display file or filesystem status

file determines filetype

info read info documents

fsck check and repair a linux filesystem.

mkfs build a linux filesystem

tune2fs adjust tuneable filesystem parameters.

/etc/opt Configuration files for add on software packages