1. tty: View your own virtual terminal
2. echo "Your server has been controlled by me, please call me immediately, account number 12312312312314123421, otherwise you will be at your own risk !!!"> / dev / pts / 1 Send a command to the terminal
3. Wall "The system will be shut down in 10 minutes" to send information to all terminals
4. ls -lS / root / sorts by file size
5. Alias eth0 = 'vim / etc / sysconfig / network-scripts / ifcfg-eth0' Set the command alias, note that single quotes are not backticks
6, cd-switch back to the previous directory
7. systemctl set-default multi-user.target sets the startup sector bit to 3 systemctl set-default graphical.target sets the startup sector bit to 5 runlevel or systemctl get-default to view the current system runlevel level 4 unused 0 shutdown 1 Single user 2 without network 6 keeps restarting
8. touch -d "20101019 08:30" test.txt creates a history file! ! !
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