Linux Commands frequently used by Linux Sysadmins

commands.md

1. ip – from Iproute2, a collection of utilities for controlling TCP/IP networking and traffic control in Linux.
2. ls – list directory contents.
3. df – display disk space usage.
4. du – estimate file space usage.
5. free – display memory usage.
6. scp – securely Copy Files Using SCP, with examples.
7. find – locates files based on some user-specified criteria.
8. ncdu – a disk utility for Unix systems.
9. pstree – display a tree of processes.
10. last – show a listing of last logged in users.
11. w – show a list of currently logged in user sessions.
12. grep – Search a file for a pattern of characters, then display all matching lines.
13. uptime – shows system uptime and load average.
14. top – shows an overall system view.
15. vmstat – shows system memory, processes, interrupts, paging, block I/O, and CPU info.
16. htop – interactive process viewer and manager.
17. dstat – view processes, memory, paging, I/O, CPU, etc., in real-time. All-in-one for vmstat, iostat, netstat, and ifstat.
18. iftop – network traffic viewer.
19. nethogs – network traffic analyzer.
20. iotop – interactive I/O viewer. Get an overview of storage r/w activity.
21. iostat – for storage I/O statistics.
22. netstat – for network statistics.
23. ss – utility to investigate sockets.
24. atop – For Linux server performance analysis.
25. Glances and nmon – htop and top Alternatives:
26. ssh – secure command-line access to remote Linux systems.
27. sudo – execute commands with administrative privilege.
28. cd – directory navigation.
29. pwd – shows your current directory location.
30. cp – copying files and folders.
31. mv – moving files and folders.
32. rm – removing files and folders.
33. mkdir – create or make new directories.
34. touch – used to update the access date and/or modification date of a computer file or directory.
35. man – for reading system reference manuals.
36. apropos – Search man page names and descriptions.
37. rsync – remote file transfers and syncing.
38. tar – an archiving utility.
39. gzip – file compression and decompression.
40. b2zip – similar to gzip. It uses a different compression algorithm.
41. zip – for packaging and compressing (to archive) files.
42. locate – search files in Linux.
43. ps – information about the currently running processes.
44. `Making use of Bash scripts. Example: ./bashscript.sh
45. cron – set up scheduled tasks to run.
46. nmcli – network management.
47. ping – send ICMP ECHO_REQUEST to network hosts.
48. traceroute – check the route packets take to a specified host.
49. mtr – network diagnostic tool.
50. nslookup – query Internet name servers (NS) interactively.
51. host – perform DNS lookups in Linux.
52. dig – DNS lookup utility.
53. wget – retrieve files over HTTP, HTTPS, FTP, and FTPS.
54. curl – transferring data using various network protocols. (supports more protocols than wget)
55. dd – convert and copy files.
56. fdisk – manipulate the disk partition table.
57. parted – for creating and manipulating partition tables.
58. blkid – command-line utility to locate/print block device attributes.
59. mkfs – build a Linux file system.
60. fsck – tool for checking the consistency of a file system.
61. whois – client for the whois directory service.
62. nc – command-line networking utility. (Also, see 60 Linux Networking commands and scripts.)
63. umask – set file mode creation mask.
64. chmod – change the access permissions of file system objects.
65. chown – change file owner and group.
66. chroot – run command or interactive shell with a special root directory.
67. useradd – create a new user or update default new user information.
68. userdel – used to delete a user account and all related files.
69. usermod – used to modify or change any attributes of an existing user account.
70. vi – text editor.
71. cat – display file contents.
72. tac – output file contents, in reverse.
73. more – display file contents one screen/page at a time.
74. less – similar to the more command with additional features.
75. tail – used to display the tail end of a text file or piped data.
76. dmesg – prints the message buffer of the kernel ring.
77. journalctl – query the systemd journal.
78. kill – terminate a process.
79. killall – Sends a kill signal to all instances of a process by name.
80. sleep – suspends program execution for a specified time.
81. wait – Suspend script execution until all jobs running in the background have been terminated.
82. nohup – Run Commands in the Background.
83. screen – hold a session open on a remote server. (also a full-screen window manager)
84. tmux – a terminal multiplexer.
85. passwd – change a user’s password.
86. chpassword
87. mount / umount – provides access to an entire filesystem in one directory.
88. systemctl – Managing Services (Daemons).
89. clear – clears the screen of the terminal.
90. env – Run a command in a modified environment.
91. cheat – allows you to create and view interactive cheatsheets on the command-line.”
92. tldr – Collaborative cheatsheets for console commands.
93. bashtop – the ‘cool’ top alternative.
94. bpytop – Python port of bashtop.