% ubuntu, linux # 更新系统 Update system sudo apt update && sudo apt upgrade # 安装软件包 Install package sudo apt install # 卸载软件包 Uninstall package sudo apt remove % 防火墙 Firewall # 查看防火墙状态 View firewall status sudo ufw status # 开启防火墙 Enable firewall sudo ufw enable # 关闭防火墙 Disable firewall sudo ufw disable # 允许特定端口 Allow specific port 示例: 80, 443 sudo ufw allow # 禁止特定端口 Deny specific port 示例: 80, 443 sudo ufw deny # 允许特定端口范围 Allow specific port range 示例: 1024-65535 sudo ufw allow # 禁止特定端口范围 Deny specific port range 示例: 1024-65535 sudo ufw deny # 允许特定 IP 地址 Allow specific IP address 示例: 192.168.1.1 sudo ufw allow from # 禁止特定 IP 地址 Deny specific IP address 示例: 192.168.1.1 sudo ufw deny from