Common Linux Commands

This article is reprinted from Linux common command, delete

System Service Management

systemctl

The systemctl command is a combination of the service and chconfig commands to manage the system.

  • Output the status of each service in the system
systemctl list-units --type=service
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  • View the running status of the service
systemctl status firewalld
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  • Close the service
systemctl stop firewalld
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  • Start the service
systemctl start firewalld
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  • Restarting the service (regardless of whether the service is up or down)
systemctl restart firewalld 
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  • Reloads the configuration without interrupting service
systemctl reload firewalld
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  • Disable service startup upon startup
systemctl disable firewalld
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  • Setting boot
systemctl enable firewalld
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File management

ls

List all files in the specified directory and the files in the root directory

Ls minus L over l is the same thing as LLCopy the code

pwd

Gets the absolute path to the current working directory

pwd
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cd

Change working directory

cd /usr/local
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date

Displays or modifies the system time and date

date '+%Y-%m-%d %H:%M:%S'
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passwd

User Sets the user password

passwd root
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su

Changing user Identity

clear

Clear screen information

man

Displays help information about a specified command

man ls
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who

  • What health level is the system in
who -r
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  • Displays the current users logged in to the system
who -buT
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free

Display system memory status in MB

free -m
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ps

  • Displays the running status of system processes
ps -ef
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  • To viewsshdRunning status of a process
ps -ef | grep sshd
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top

View live active processes, similar to Windows task Manager.

mkdir

Create a folder mkdir /mydata

more

Used to view files in pages, columns such as 10 lines per page to view boot.log files

more -c -10 /var/log/boot.log
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cat

View a file, such as a Linux startup log file, and label the line number

cat -Ab /var/log/boot.log
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touch

This command is used to create files, such as text.txt files

touch text.txt
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rm

  • Delete the file
rm text.txt
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  • Forcibly delete a directory and its subdirectories
 rm -rf testdir
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cp

Used to copy files, such as directory test1 to directory test2

cp -r /mydata/test1 /mydata/test2
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mv

Used to move or overwrite files