Unit firewalld.service could not be found. 防火牆命令找不到

# systemctl status firewalld
Unit firewalld.service could not be found.
# systemctl stop firewalld.service
Failed to stop firewalld.service: Unit firewalld.service not loaded.

解決辦法：

yum install firewalld
參考鏈接：https://blog.csdn.net/bo123_/article/details/101484987

查看防火牆狀態
firewall-cmd --state
systemctl status firewalld
停止firewall
systemctl stop firewalld.service
禁止firewall開機啟動
systemctl disable firewalld.service