CompTIA A+ 1102 Linux Features and Commands

Linux Command Line Options (list)

- Terminal

- XTerm

- (etc.)

Linux Commands

- similar to Mac OS commands

"man" (command)

shows the manual for a Linux command

"ls" (command)

- lists directory contents

- similar to "dir" in Windows

- may support color coding

- blue indicates a directory

- red indicates an archive file

- add "-l" at the end to view a longer output

- adding "-l | more" will present a page by page view

- use "q" or key in ctrl-c to exit this view

"pwd" (command)

- prints the working directory's name (path)

"mv"

- move or rename a file

- "mv [source] [destination]

- for example, "mv first.txt second.txt"

"cp" (command)

- copies a file

- "cp [source] [destination]"

"rm" (command)

- removes a file or directory

- a directory must be empty to be removed, or must be removed with "-r"

"chmod" (command)

- changes the mode (permissions) of a file system object

- "chmod [mode] [file]"

- for example, "chmod 744 script.sh"

- this would grant the user rwx, group r--, and others r--

- can also use letters to specify the mode

Linux File System Modes (list)

- r (read)

- w (write)

- x (execute)

Linux File System Mode Cheat Sheet (image)

"chown" (command)

- changes a file's owner and/or group

- requires root permissions and credentials

- "sudo chown [owner]:[group] [file]"

- "[group]" is optional

"su" (command)

- become the super user

- grants administrative (root) privileges

"sudo" (command)

- execute a command as the super user

- grants administrative (root) privileges, but only when using "sudo" in front of a command

"apt-get" (command)

- advanced packaging tool

- handles the management of application packages

- "sudo apt-get [install/update/remove] [application]"

"yum" (command)

manages RPM (Red Hat) packages

"ip" (command)

manage the network interface

Commonly Used "ip" Commands (list)

- "ip address"

- "ip route"

"ip address" (command)

- view the interface address

- for example, "sudo ip address add [ip address and subnet mask] dev [adapter name]"

- configures the IP address of an interface

"ip route" (command)

- view the IP routing table

"df" (command)

- view file systems and free space

- presented in blocks

- use "df -h" to view in human-readable sizes

"grep" (command)

- used to find text in a file or files

- "grep [text pattern] [file]"

"ps" (command)

- view the current processes

- use "ps -e" to view all processes, including those for other users

"top" (command)

- view resource utilization

- includes a summary of the overall load

- presented in one, five, and fifteen minute intervals

"find" (command)

- find a file by the name or file extension

- "find . -[name] [file and extension]"

- finds files with that specific extension

- the "." indicates that the search will begin at the current folder (the working folder)

"dig" (command)

- lookup information from DNS servers

- provides detailed domain information

"cat" (command)

- concatenate files

- "cat [first file and extension] [second file and extension]"

- copies a file or files to another file

"nano" (command)

provides a full-screen text editor

"tar" (command)

- used to create and manage tape drive archives and backups

- can be used for any type of file

- easy to script into a backup schedule

"rsync" (command)

- provides a utility for syncing files between storage devices

- can be instant or scheduled

Software Center

Linux's version of the Mac OS App Store

Anti-Virus and Anti-Malware on Linux

- no built-in options

- Clam is the recommended third-party anti-virus

- open-source

"samba"

- file server utility

- often used to add SMB (Server Message Block) to Linux systems

- implement file and printer sharing

- integrate with Active Directory

- integrates Linux into a Windows environment