啟動服務：systemctl start vsftpd.service
關閉服務：systemctl stop vsftpd.service
重啟服務：systemctl restart vsftpd.service
顯示服務的狀態：systemctl status vsftpd.service
在開機時啟用服務：systemctl enable vsftpd.service
在開機時禁用服務：systemctl disable vsftpd.service
查看服務是否開機啟動：systemctl is-enabled vsftpd.service
查看已啟動的服務列表：systemctl list-unit-files|grep enabled
查看啟動失敗的服務列表：systemctl --failed
centos8 ：
查看防火牆狀態：systemctl status firewalld.service
開啟防火牆：systemctl start firewalld.service
關閉防火牆：systemctl stop firewalld.service
禁用防火牆：systemctl disable firewalld.service
systemctl service update-rc.d三者的區別
https://blog.csdn.net/qq_37993487/article/details/79868857