Linux Command Cheat Sheet for System Administrators

Have you ever been in a spelling bee? Or remember back to English class where you'd have a weekly vocabulary list of words and their corresponding definitions?

Well I started doing something similar when starting my Linux journey, made a little cheat sheet that occasionally I would add too and put up on the side of my screen when in the terminal. The more I used used the list the more it grew, and I still review it every other day to jog my memory on common linux commands that are useful when navigating the terminal.

This is an ongoing cheat sheet (might update the article as the sheet grows), I hope someone out there finds it useful!

1) ip - used to show or manipulate routing, devices, and tunnels?

2) ls - list the contents of a directory

3) df - displays the amount of disk space used

4) du - display a list of all the files along with their respective sizes

5) free - use to get a detailed report on the system's memory usage

6) scp - securely copy files or directories over ssh

7) find - locates files using user-defined criteria

8) ncdu - provides a useful and convenient way to view disk usage?

9) pstree - used to show running processes in a tree (data structure)

10) last - displays a list of the most recent logged-in people?

11) w - display a list of the currently logged-in user sessions?

12) grep - searches a file for a pattern of characters and displays all lines that match

13) awk - a scripting language used for text processing?

14) sed - stream editor used to preform lots of functions on files, like searching, find and replace, insertion, or deletion

15) cut - allows you to cut out sections of a specified file or piped data and print the result to standard output

16) sort - used to sort files

17) uniq - used to extract uniq occurrences

18) tr - utility for translating or deleting characters?

19) diff - used to display differences in files by comparing line by line

20) uptime - displays the system uptime as well as the load average?

21) top - shows a real-time view of running processes in Linux

22) vmstat - used to obtain information about memory, system processes, paging, interrupts, block I/O, disk, and CPU scheduling?

23) htop - a process viewer and manager that is interactive?

24) pcp-dstat - allows you to view all of your system resources instantly. All-in-one vmstat, iostat, netstat, and ifstat utility

25) lftop - network traffic viewer?

26) nethogs - is a network traffic analyzer?

27) iotop - is an interactive I/O viewer. Get a snapshot of storage r/w activity?

28) iostat - provides statistics on storage I/O

29) netstat - used to show network statistics

30) ss - a simpler and faster version of the now obsolete netstat command

31) pcp-atop - a tool for monitoring system resources in Linux

32) ssh - secure protocol used as the primary means of connecting to Linux servers remotely?

33) sudo - run commands with administrative privileges

34) cd - navigate between directories?

35) pwd - displays the current directory path

36) cp - copy files and directories

37) mv - move file or directories?

38) rm - deletes files and directories?

39) mkdir - create new directories

40) touch - used to create, update a computer file or directory's access

41) man - used to read system reference manuals

42) apropos - searches manual page names and descriptions for a user supplied keyword

43) rsync - remote file transfer and synchronization?

44) tar - is an archive utility

45) gzip - use for compression and decompression of files?

46) b2zip - a compression utility comparable to gzip. It employs a distinct compression algorithm

47) zip - used for file packaging and compression (archiving)

48) locate - search for files?

49) ps - allows you to list the status of processes running on your system easily?

50) cron - execute scheduled tasks

51) nmcli - used to display network device status, create, edit, activate/deactivate, and delete network connections?

52) ping - send an ICMP echo request to network hosts

53) traceroute - examine the path packets follow to reach a specific host?

54) mtr - a network diagnostic tool, a combination of ping and traceroute commands

55) nslookup - interactively query internet name servers (NS)

56) host - used for DNS (Domain Name System)

57) dig - DNS lookup tool

58) wget - download files through HTTP, HTTPS, FTP, and FTPS

59) curl - data transport via several network protocols (can handle more protocols than wget)

60) dd - used to convert and copy files

61) fdisk - modify the disk partition table

62) parted - used to create and manipulate partition tables

63) blkid - utility for finding and printing block device attributes

64) mkfs - create a linux file system?

65) fsck - utility for determining the consistency of a file system

66) nc - used for just about anything under the sun involving TCP or UDP

67) umask - returns, or sets the value of the system's file mode creation mask?

68) chmod - alters the access rights of file system objects

69) chown - alter the owner and group of a file

70) chroot - used to change the root directory

71) useradd - create a new user or alter the default information for a new user

72) userdel - used to delete a user account and all associated files

73) usermod - used to edit or change any existing user account's properties

74) vi - text editor?

75) cat - displays the contents of a file

76) tac - reverse output file contents

77) more - show file contents one screen/page at a time

78) less - identical to more, but with more features

79) tail - used to show the last few lines of a text file or piped data

80) head - used to show the first few lines of a text file or piped data

81) dmesg - displays the kernel ring's message buffer

82) journalctl - used to view systemd, kernel, and journal logs

83) kill - terminates a process

84) killall - sends a kill signal to all instances of a specific process

85) sleep - pauses program execution for a given amount of time

86) wait - suspend script execution until all background jobs have been completed

87) nohup - short for no hang up, keeps processes running even after exiting the shell or terminal

88) screen - keep a remote server session open (also functions as a full screen window manager)

89) tmux - a terminal multiplexer?

90) passwd - change the password of a user?

91) clear - clears the terminal's screen

92) env - run a command in an altered environment?

93) mount - used to mount the filesystem sound on a device to big tree structure (the linux file system) rooted at '/'

94) unmount - unmount a previously mounted device, directory, file, or file system

95) systemctl - used to control and manage systemd and services