Linux Common commands

1. View Ipifconfig or IP A2. Restart the reboot3. Shutdown shutdown-h now4. Stop CTRL+C5. Restart the network or one of the Services service network restart II. directories and Operations commands

6. View the working directory

pwd

7. Switch working directory What does the interview mean, note that it is not open! Not open! Not open!

CD [Directory location]

8. Display Directory Contents

ls [-a\-l\-al]

9. Create a new directory

mkdir-p [path] Directory name

-P is used to create a multi-level directory, if and in the path, the folder will be created with the directory

10. Space occupancy of statistical catalogues and documents

du [options] [directory or file name]

-A: All files are included in the statistics, not just the statistics directory

-

H: Display information in more readable byte units (k, m), etc.

-S: Counts the total amount of space occupied by each parameter

Third, the file Operation command

11. Create a new empty file or update a file time stamp

Touch file name

12. View File Types

File

file name

13. Copying Files or directories

CP [option] source file or directory directory file or

directory

-

R: Recursively replicate entire directory tree

-P: Keep the properties of the source file

unchanged

-

F: Force overwrite the target file or directory with the same name

-I

: reminders when files or directories need to be overwritten

14. Delete Files or directories

RM [Options] File or directory

-

F: Force deletion of files or directories, no reminders

-I

: Remind users to confirm when deleting files or directories

-

R: Recursively delete entire directory tree

15. Move a file or directory

mv [options] source file destination file

If the destination file location is the same as the source file location, it is equivalent to renaming

 

16. Find the Linux command file and display the location (the search scope is specified by the PATH environment variable)

which command or program name

17.whereis

18. Find File locate (faster search in the background database)

Locate file name

/var/lib/mlocate Database location, updated daily

ipdatedb Updating the database

 

19.find Lookup (compare wasted resources)

used to find files or directories

Find

search scopes Find what to look for

Conditions:

-name: File name

-size: File size

-user: File Properties

-type: File type,

Example: find/var/log/-mtime +10

Description:

-10:10 files modified within the day

documents modified from 10:10 day

files modified +10:10 days ago

atime: File access time

ctime: Changing file properties

mtime: Modifying file contents

20. Establishing a connection for a file or directory

LN [-s] source file or directory link file or directory

-S: Create a symbolic link file, omit this key to establish a hard link

 

about linked Files

Symbolic Link: The path to the original file, called the soft link

Hard Links: points to the data storage location for the original file

You cannot establish a hard-link file for a directory,

hard links must be in the same partition as the original file

 

with window for

Soft connect = Shortcut key: Source file plus absolute path must not be wrong

hard link = copy

 

Additional: SCP from remote replication

Example: The 192.168.62.10 above the/root/folder, download to the local/home/new/, using the remote side of the root login

scp-r [email protected]:/root//home/new/

 

Iv. file Contents Operation 21. Display the full contents of the file CAT/absolute path 22. View a portion of the file at the beginning of the document (default 10 lines) head-n file name 23. View part of the end of the file (default 10 lines) tail-n file name Tail-f File name 24. Information about the number of words in a statistical file WC [Options] Destination file-L: Count Rows-W: Count the number of words-C: Statistics bytes 25. Finds and displays rows in a file that contain the specified string grep [options] Find file Target file-I: Ignore case when lookup: reverse lookup, Enter a row lookup condition that is not equal to the lookup condition the string to find is enclosed in double quotation marks "^ ..." to indicate that: The beginning of "... $" indicates a ... The end "^$" represents a blank line | : A pipeline, which can be interpreted as the result of the first condition lookup, as the source file for the second condition Lookup 26. Compress and decompress tar options archive file name source file or directory options:-C: Create a package file in. tar format-x: Unpack the. tar format package file-V: Output details-F: Use archive file-Z: Call Gzip-j: Call bzip2 compression: Tar jvcf file name. tar.bz2 source file name extract: Tar JVXF file name. tar.bz2 source file name v. User account Management 1. User accounts Super User: Root ordinary User program User 2. Group account Basic Group (private Group) additional group (total group) 3.UID and GID user representation Number group representation number 27. User account File passwd

file location/etc/passwd stored account basic information

Example: text:x: 500:500:text Demo:/home/text:/bin/bash

user account name: Password placeholder: uid:gid: Full Name: Host directory: Login Shell information

Password string/expiration information location etc/shadow28. Add account useradd option user name Option-u: Specify UID Tag number-D: Specify the host directory, default is/home/ User Name-E: Specify the account Expiration Time-G: Basic group name (or UID)-G: Additional group name (or GID)-s: Specify user's login information 29. Account initial profile copied from/etc/skel 30. Set/change user password passwd options Username-D: Clear password-L: Lock User name-S: View status-u: Unlock username 31. Modify the Account attribute Usermod (Note: The modified user cannot be logged in when the login name is modified) usermod option Username-l (lowercase): Change login name new username in front Old username in the rear-L: Lock user account-U: Unlock user account 32. Delete user account Userdel [-r] User name-r: Indicates the host directory of the connecting user is deleted. Group account Management/etc/group Save group account basic information/etc/gshadow Save password information for group account admin:x: 4:root, adm,adeeee group account name UID GID Group Member list 33. Add group account Groupadd

Groupadd [-G GID] group account name

 

Modify group name: Groupmod-n new name Original name

Modify group number: Groupmod-g GID Group name

 

34. Add/Remove Group

members

gpasswd option group account name

-

A: Adding a user member to a group GPASSWD-A user name group account

-

D: Delete a user member from within a group

-M: Defines a list of group members, separated by commas

 

Groupdel Group account name

 

Vii. File/directory Permissions

access rights: Read, Write, execute

Attribution:

Owner

: The user account that owns the file or directory

array: The group account that owns the file or directory

Example:--rw-r--r--| root root 34298 04-02 00:23

First-: File type-file D directory l Soft Connect file access is the primary array

 

access Rights

Read R 4

Write W 2

perform x 1

 

u file owner G file belongs to group O other users

 

35. Set file, directory permissions

chmod u (g, O, a) + (-, =) R (w, x) file

chmod nnn File

nnn for 421

-r: Recursively modifies permissions for all files and subdirectories under the specified directory

 

36. Set the attribution of files and directories

chown Master File

chown: Genus Group File

chown Owner: Array file

 

37. Additional Bit Permissions

Set bit Permissions

Purpose: 1. For executable file settings, the permission character is "s"

2. When other users execute the file, they will have the permissions of the owner or group of users

chmod u+s

 

VIII. Process Management

38. Viewing Static Process statistics

PS aux

ps-elf

A: Displays all process information under the current terminal

u: Output process information in a user-oriented format

x: Displays process information for the current user under all terminals

 

Filter a process

Ps-ef | Gerp xxxxx39. Viewing dynamic process rank information Top 40. Show relationships among processes in a tree structure pstree-p: List The pid-u of the process: list the corresponding user name of the process-A: Lists the completion commands for the process 41. To terminate the process run CTRL + C Interrupt the executing command kill, killall-9 Nine, the configuration format of the scheduled management instance 1.crontab task

* Indicates any time within the range

, which represents multiple discontinuous points of time for the interval

-Represents a time range for a connection

/Specify the time frequency of the interval

 

* * * * *

Timeshare Month Week

 

Editor: Crontab-e [-u user Name]

View: Crontab-l

Delete: Crontab-r

 

Example: Automatically open sshd service 7:50 every day, 22:50 close

crontab-e

7 * * */sbin/service sshd start

* * * *

/etc/init.d/sshd sshd Stop

2. Automatic support at specified date, point in time some of the pre-set command operations, belong to a scheduled task at [hh:mm] [YY-MM-DD] Press Ctrl+d submit

Linux Common commands