Linux Operations Learning -3--2016 July 24

Format Description:

Operation

Concept

Command

Description and examples

Three-1

Touch/etc/nologin so that ordinary users can not log on (create a file, delete to log in) Ll/etc/nologin view that file-rm-f/etc/delete that file init 0 (Shutdown) 3 5 6 (restart) free view memory re Set fix (when garbled) Straceltracetouch ' date +%f '. Log creates a file with a date named Touch F1 F2 F3touch f{1,2,3,4,5}. {txt,log} Create file Rm-f f{1,2,3,4,5}. {Txt,log} Delete one rm-f f * Delete Two

Use Help

Whatis installed system can not be immediately used, the background is automatically created (about 1 hours) Makewhatis 6 version created Whatis database mandb 7 Create Whatis database Man-f and Whatis explicit an effect help + command View internal command assist man Bach see the Help command for all commands +--help view external commands help command +--h Some external commands support shorthand help date-d yesterday show yesterday date date-d yesterday +%fdate-d "-2 Day" +%f display ago Days Date date-d ' +2 day ' +%f Show day after date +%j How many days has it been this year BC system comes with calculator ntpdate +ip with a computer time synchronization passwd Change password

Man Help Handbook

Man 5 passwd See the fifth chapter of passwd help Whatis passwd view passwd command information. Contains chapter numbers search keywords in man help page: \+ keyword press Q to exit apropos passwd to search Whatis library for keywords passwd

Command +& This command is performed in the background, and can then do something else

Practice:

Timer shutdown Issue Modify login prompt display Terminal number hostname

Navigating the Info page

Google search

OpenStack filetype:pdf search for PDF files with OpenStack keywords
RHCA Site:redhat.com/docs searching for docs files within the development site

History

History! + numbering repeats the commands in the history!! Ditto! -1 Ibid. ctrl+p ibid.? Go executes the last command executed with "Go" ctrl+r Search duration Command

Command invariant parameter with previous parameter: ESC let go +.
or press ALT +.
Or! $

!^ the first parameter of the previous command! $ last parameter on a command! * All parameters of the previous command! : 2 The second parameter of the previous command! 128:^ the first parameter of the 128th command! 128:2 the second parameter of the 128th command! l:^ the first parameter in the L-history-c clears the memory history history-d 22 deletes the command specified in history history-a writes the new action to the history file rm-f. bash_history Delete the history file (deleting the file before deleting the record) Histt imeformat= '%F%T ' history command execution time display file path:/etc/profile add: histtimeformat= "%F%T" Export Histtimeformatzz Save changes: Wq Save after exit execution: source /etc/profile changes take effect or exit after exit re-login changes take effect

Defining aliases

Alias mm= "CD" MM when using CD

Three-2 Tree

Loading tree and query:

Tree-d Show only Directories

290 2016-07-25 17:15:48 CD/
291 2016-07-25 17:15:57 cd/media/
292 2016-07-25 17:16:04 DF
293 2016-07-25 17:16:29 CD CentOS6.8final/294 2016-07-25 17:16:38 ls
297 2016-07-25 17:17:58 CD Packages
298 2016-07-25 17:18:02 ls
299 2016-07-25 17:18:18 RPM-IVH tree-1.5.3-3.el6.x86_64.rpm

2016-07-25 17:18:30 Tree 302 2016-07-25 17:19:11 tree-d-L 1 303 2016-07-25 17:19:19 cd/304 2016-07-25 1 7:19:21 tree-d-L 1 305 2016-07-25 17:19:44 tree-d 306 2016-07-25 17:20:06 tree-d-L 2 find-name ' tom* '-ls Find files by file name

Linux Operations Learning -3--2016 July 24