RHEL 9 查看防火墙状态： systemctl status firewalld 如果防火墙被关闭，启动： sudo systemctl start firewalld sudo systemctl enable firewalld 添加规则： sudo firewall-cmd --permanent --zone=public --add-rich-rule='rule family="ipv4" source address="192.168.0.0/24" port port="3306" protoc…