理解 VPN 的基本概念

VPN（Virtual Private Network）主要用于在无需物理连接的情况下，将内部网络（如内部服务器）与外部网络（如互联网）连接起来，在 VPS 上构建 VPN，通常是将 VPS 内的云服务器与外部VPN服务（如 OpenVPN、VPN中国区等）实现连接。

准备 VPS 的配置文件

VPS 的配置文件（如 config/vps-config）通常包含以下信息：

• 服务器的 IP 地址
• 服务器的端口
• 服务器的名称
• 环境变量的设置（如 SSL/TLS 部署模式）

在构建 VPN 架构之前，您需要确保 VPS 的配置文件是完整的，以便在后续的配置中使用这些信息。

安装VPN 系统

在 VPS 上构建 VPN，通常需要使用云服务器（如 AWS、Azure、Google Cloud 等）来提供 VPN 服务，以下是常见云服务器和对应的VPN服务：

• AWS：OpenVPN（AWS OpenVPN）
• Azure：Azure OpenVPN
• Google Cloud：OpenVPN（Google Cloud VPN）

您需要选择一个适合的云服务器和对应的VPN服务。

配置 VPS 的配置文件

在配置文件中,您需要加入以下信息：

• VPN 容器地址：在配置文件中，添加以下内容：

  container: openvpn
  port: 443
  name: local
  name-prefix: 8
  http-truncated: true
  https-truncated: true

  这里 "http-truncated" 和 "https-truncated" 表示使用VPN来阻止外部网站访问内部服务器，同时允许外部网站使用 HTTP/HTTPS 连接。

安装 VPN 系统

使用以下命令安装 VPN 系统到 VPS：

sudo apt-get install openvpn-openvpn

配置 VPS 的防火墙

为了安全起见,建议在 VPS 上配置防火墙，阻止所有外部访问，以下是一个示例配置：

firewall:
  type: firewalld
  interface: 8
  username: admin
  password: admin
  port: 8
  protocol: http
  protocol-option: secure
  allow: all
  allow-flow: yes
  allow-skip: yes
  allow-skip-flow: yes
  allow-redirect: yes
  allow-skip-redirect: yes
  allow-redirect-keepalive: yes
  allow-skip-redirect-keepalive: yes
  allow-redirect-redirect: yes
  allow-skip-redirect-redirect: yes
  allow-skip: yes
  allow-skip-flow: yes
  allow-redirect: yes
  allow-skip-redirect: yes
  allow-skip-flow: yes
  allow-redirect-keepalive: yes
  allow-skip-redirect-keepalive: yes
  allow-skip-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-flow-sysid: yes
  allow-skip-redirect-sysid: yes