Nginx 完全教程

Nginx 完全教程

从零开始掌握 Nginx 的安装、配置与运维。

---

01. Nginx 简介

Nginx（发音 "engine-x"）是一个高性能的 HTTP 和反向代理服务器，由 Igor Sysoev 于 2004 年首次发布。它以事件驱动、异步非阻塞的架构闻名，能够以极低的内存消耗处理数万并发连接。

Nginx 能做什么？

• HTTP 服务器 — 高效提供静态文件服务
• 反向代理 — 将请求转发给后端应用服务器
• 负载均衡 — 在多台后端之间分发流量
• SSL/TLS 终端 — 处理 HTTPS 加密解密
• API 网关 — 路由、限流、鉴权
• 邮件代理 — IMAP/POP3/SMTP 代理

Nginx vs Apache

特性	Nginx	Apache
架构模型	事件驱动 / 异步非阻塞	进程 / 线程驱动
并发性能	极高（C10K+）	中等
内存占用	低	相对较高
静态文件	极快	良好
动态内容	需借助外部（PHP-FPM等）	内置 mod_php
配置风格	集中式、声明式	.htaccess 分散式

---

02. Linux 安装与启动

Ubuntu / Debian

# 更新软件源并安装
sudo apt update
sudo apt install -y nginx
​
# 启动 & 设为开机自启
sudo systemctl start nginx
sudo systemctl enable nginx
​
# 验证安装
nginx -v

CentOS / RHEL / Fedora

# CentOS 7
sudo yum install -y epel-release
sudo yum install -y nginx
​
# CentOS 8+ / Fedora
sudo dnf install -y nginx
​
sudo systemctl start nginx
sudo systemctl enable nginx

macOS (Homebrew)

brew install nginx
brew services start nginx

Docker

docker run -d --name nginx \
  -p 80:80 \
  -v /path/to/html:/usr/share/nginx/html \
  -v /path/to/nginx.conf:/etc/nginx/nginx.conf \
  nginx:stable

常用管理命令

nginx -t              # 测试配置语法
nginx -T              # 测试并输出完整配置
nginx -s reload       # 平滑重载（不中断服务）
nginx -s stop         # 快速停止
nginx -s quit         # 优雅停止
nginx -s reopen       # 重新打开日志
nginx -V              # 查看编译参数

提示 生产环境推荐使用 nginx -s reload 来应用配置变更，该操作是零停机的。

---

03. Windows 安装与配置

Nginx 官方提供 Windows 预编译包。虽然 Windows 版主要用于开发和测试，但掌握其安装方法对本地开发非常有用。

注意 Windows 版 Nginx 不支持 select 以外的事件模型，性能远不如 Linux 版。 生产环境请使用 Linux。

方法一：下载官方压缩包

0. 下载 Nginx访问 nginx.org/download，下载 Stable version 的 Windows zip 包。
1. 解压到目标目录建议解压到 C:\nginx，路径中不要包含中文或空格。
2. 启动 Nginx

cd C:\nginx
.\nginx.exe
​
# 验证：浏览器访问 http://localhost
tasklist /fi "imagename eq nginx.exe"

Windows 管理命令

cd C:\nginx
.\nginx.exe -t             # 测试配置
.\nginx.exe -s reload      # 重载配置
.\nginx.exe -s stop        # 快速停止
.\nginx.exe -s quit        # 优雅停止

重要 Windows 没有 systemctl ，Nginx 不会自动作为服务运行。关闭命令行后 Nginx 仍在后台，需用 nginx -s stop 或任务管理器终止。

端口冲突排查

netstat -ano | findstr ":80 "
iisreset /stop             # 停止 IIS
net stop W3SVC             # 停止 WWW 服务

方法二：Chocolatey

choco install nginx -y

方法三：Scoop

scoop bucket add main
scoop install nginx

方法四：Docker Desktop

version: "3.8"
services:
  nginx:
    image: nginx:stable
    ports: ["80:80", "443:443"]
    volumes:
      - ./html:/usr/share/nginx/html
      - ./nginx.conf:/etc/nginx/nginx.conf:ro
    restart: unless-stopped

注册为系统服务（NSSM）

# 下载: https://nssm.cc/download
nssm install Nginx "C:\nginx\nginx.exe"
nssm set Nginx AppDirectory "C:\nginx"
nssm set Nginx Start SERVICE_AUTO_START
nssm start Nginx

Windows 配置示例

worker_processes 1;

events { worker_connections 1024; }

http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile  on;
    gzip     on;

    server {
        listen 80;
        server_name localhost;

        location / {
            root html;
            index index.html;
        }

        location /api/ {
            proxy_pass http://127.0.0.1:3000;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
        }
    }
    include conf.d/*.conf;
}

各平台安装方式对比

平台	推荐方式	命令	场景
Ubuntu/Debian	apt	apt install nginx	生产
CentOS/RHEL	dnf	dnf install nginx	生产
macOS	Homebrew	brew install nginx	开发
Windows	zip	下载解压	开发
Windows	Chocolatey	choco install nginx	开发
Windows	Scoop	scoop install nginx	开发
Windows	Docker	docker run nginx	一致性

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04. 核心概念

请求处理模型

Nginx 采用一个 Master 进程 + 多个 Worker 进程的模型。

Client Request
   │
   ▼
┌──────────────────────────────┐
│       Master Process         │
│   (读取配置, 管理 Worker)     │
└──────┬───────────┬───────────┘
       │           │
  ┌────▼────┐ ┌────▼────┐
  │Worker 1 │ │Worker 2 │
  │ (epoll) │ │ (epoll) │
  └────┬────┘ └────┬────┘
       │           │
  ┌────▼────┐ ┌────▼────┐
  │Backend A│ │Backend B│
  └─────────┘ └─────────┘

关键目录

路径	Linux	Windows
主配置	/etc/nginx/nginx.conf	C:\nginx\conf\nginx.conf
附加配置	/etc/nginx/conf.d/	C:\nginx\conf.d\
站点根	/var/www/	C:\nginx\html\
日志	/var/log/nginx/	C:\nginx\logs\
MIME	/etc/nginx/mime.types	C:\nginx\conf\mime.types

---

05. 配置文件结构

user              nginx;
worker_processes  auto;
error_log         /var/log/nginx/error.log warn;
pid               /var/run/nginx.pid;

events {
    worker_connections 1024;
    use epoll;
}

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;
    sendfile    on;
    gzip        on;
    include     /etc/nginx/conf.d/*.conf;

    server {
        listen      80;
        server_name example.com;
        root        /var/www/example;
        location /      { index index.html; }
        location /api/  { proxy_pass http://127.0.0.1:3000; }
    }
}

配置层次

main        ← 全局
├── events    ← 事件
└── http      ← HTTP
      ├── server  ← 虚拟主机
      │   └── location ← URL
      └── upstream ← 后端组

注意 修改配置后务必先执行 nginx -t 测试语法。

---

06. 虚拟主机

server {
    listen 80;
    server_name site-a.com www.site-a.com;
    root /var/www/site-a;
    location / { try_files $uri $uri/ =404; }
}

# 默认服务器 — 处理未匹配请求
server {
    listen 80 default_server;
    server_name _;
    return 444;
}

---

07. Location 路由匹配

语法	类型	优先级
= /path	精确匹配	最高
^~ /path	前缀匹配	高
~ pattern	正则（区分大小写）	中
~* pattern	正则（不区分）	中
/path	普通前缀	低

实战示例

location = /                    { proxy_pass http://127.0.0.1:3000/home; }
location ~* .(js|css|png|jpg)$  { expires 30d; access_log off; }
location ^~ /api/                { proxy_pass http://backend; }
location /                       { try_files $uri $uri/ /index.html; }
location ~ /.                    { deny all; }

try_files try_files $uri$uri/ /index.html — 先尝试文件 → 再尝试目录 → 都不存在返回 index.html（适合 SPA）。

---

08. 反向代理

server {
    listen 80;
    server_name api.example.com;
    location / {
        proxy_pass         http://127.0.0.1:3000;
        proxy_set_header   Host $host;
        proxy_set_header   X-Real-IP $remote_addr;
        proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header   X-Forwarded-Proto $scheme;
        proxy_connect_timeout 60s;
        proxy_read_timeout    60s;
    }
}

---

09. 静态资源服务

server {
    listen 80;
    root /var/www/static;
    sendfile on;
    gzip on;
    gzip_types text/plain text/css application/javascript
               application/json image/svg+xml font/woff2;

    location ~* .(js|css|png|jpg|svg|woff2)$ {
        expires 30d;
        add_header Cache-Control "public, immutable";
    }
    location ~ /. { deny all; }
}

---

10. HTTPS / SSL

Let's Encrypt

sudo apt install certbot python3-certbot-nginx
sudo certbot --nginx -d example.com
echo "0 3 * * * certbot renew --quiet" | sudo crontab -

手动配置

server {
    listen 80;
    server_name example.com;
    return 301 https://$host$request_uri;
}

server {
    listen 443 ssl http2;
    server_name example.com;
    ssl_certificate      /etc/letsencrypt/live/example.com/fullchain.pem;
    ssl_certificate_key  /etc/letsencrypt/live/example.com/privkey.pem;
    ssl_protocols        TLSv1.2 TLSv1.3;
    ssl_prefer_server_ciphers on;
    add_header Strict-Transport-Security "max-age=63072000; includeSubDomains" always;
    root /var/www/example;
}

---

11. 负载均衡

算法	指令	说明
轮询	—	按顺序分配
加权轮询	weight=N	按权重分配
IP Hash	ip_hash	同 IP 同后端
最少连接	least_conn	最少连接优先

upstream backend {
    server 10.0.0.1:8080 weight=3;
    server 10.0.0.2:8080 weight=2;
    server 10.0.0.3:8080 backup;
}

server {
    listen 80;
    location / {
        proxy_pass http://backend;
        proxy_next_upstream error timeout http_502 http_503;
    }
}

---

12. 缓存配置

proxy_cache_path /var/cache/nginx
    levels=1:2 keys_zone=my_cache:10m
    max_size=1g inactive=60m use_temp_path=off;

location / {
    proxy_pass http://backend;
    proxy_cache my_cache;
    proxy_cache_valid 200 302 10m;
    proxy_cache_valid 404 1m;
    add_header X-Cache-Status $upstream_cache_status;
}

---

13. Rewrite 规则

# 强制 www
server {
    listen 80;
    server_name example.com;
    return 301 http://www.example.com$request_uri;
}

# URL 美化
rewrite ^/article/(\d+)$ /article.php?id=$1 last;

# 旧路径重定向
rewrite ^/old-page$ /new-page permanent;

---

14. WebSocket 代理

location /ws/ {
    proxy_pass http://ws_backend;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
    proxy_read_timeout 3600s;
    proxy_buffering off;
}

---

15. 安全加固

安全响应头

server_tokens off;
add_header X-Frame-Options "SAMEORIGIN" always;
add_header X-Content-Type-Options "nosniff" always;
add_header X-XSS-Protection "1; mode=block" always;
add_header Referrer-Policy "strict-origin-when-cross-origin" always;

限流

limit_req_zone $binary_remote_addr zone=api:10m rate=10r/s;

location /api/ {
    limit_req zone=api burst=20 nodelay;
    limit_req_status 429;
    proxy_pass http://backend;
}

---

16. 性能优化

worker_processes auto;
worker_rlimit_nofile 65535;

events {
    worker_connections 10240;
    multi_accept on;
    use epoll;
}

http {
    sendfile    on;
    tcp_nopush  on;
    tcp_nodelay on;
    keepalive_timeout  65;
    keepalive_requests 1000;
    gzip on;
    gzip_comp_level 4;
    gzip_static on;
}

---

17. 日志与监控

JSON 日志

log_format json_log escape=json
    '{"time":"$time_iso8601","addr":"$remote_addr",'
    '"method":"$request_method","uri":"$request_uri",'
    '"status":$status,"time_s":$request_time}';

access_log /var/log/nginx/access.json json_log;

常用变量

变量	说明
$remote_addr	客户端 IP
$request_uri	完整 URI
$status	状态码
$request_time	处理时间
$upstream_cache_status	缓存状态

---

18. 常见问题

Q: 配置修改后不生效？

先 nginx -t 测试语法，再 nginx -s reload 重载。

Q: 502 Bad Gateway？

• 后端服务是否运行
• proxy_pass 地址端口是否正确
• 防火墙是否放行
• 查看 error.log

Q: 504 Gateway Timeout？

proxy_connect_timeout 120s;
proxy_read_timeout    120s;

Q: 413 Request Entity Too Large？

client_max_body_size 100m;

Q: Windows 启动失败？

• 检查 80 端口占用：netstat -ano | findstr ":80"
• 运行 nginx -t 检查配置
• 路径中不要有中文或空格
• 以管理员权限运行

Q: CORS 跨域配置？

location /api/ {
    add_header Access-Control-Allow-Origin $http_origin always;
    add_header Access-Control-Allow-Methods "GET, POST, PUT, DELETE, OPTIONS" always;
    add_header Access-Control-Allow-Headers "Authorization, Content-Type" always;
    if ($request_method = OPTIONS) { return 204; }
    proxy_pass http://backend;
}

---

学习资源

• Nginx 官方文档
• Nginx GitHub
• Nginx Admin's Handbook
• NSSM

---

<!DOCTYPE html>
<html lang="zh-CN" data-theme="dark">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Nginx 完全教程</title>
<link rel="preconnect" href="https://fonts.googleapis.com">
<link href="https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@300;400;600;700&family=Noto+Serif+SC:wght@400;600;700&family=DM+Sans:wght@400;500;700&display=swap" rel="stylesheet">
<style>
  :root, [data-theme="dark"] {
    --bg: #0a0e14; --bg-surface: #111820; --bg-card: #151d28;
    --bg-code: #0d1117; --accent: #00e59b; --accent-dim: #00e59b33;
    --accent-glow: #00e59b15; --text-primary: #e6edf3;
    --text-body: #b0bec5; --text-muted: #5c6b7a;
    --border: #1e2a38; --border-accent: #00e59b44;
    --tag-blue: #58a6ff; --tag-orange: #f0883e; --tag-purple: #bc8cff;
    --tag-red: #ff7b72; --tag-yellow: #e3b341;
    --info-bg: #00e59b0d; --info-text: #b0f0d8;
    --warn-bg: #e3b3410d; --warn-text: #f0dca0;
    --danger-bg: #ff7b720d; --danger-text: #ffc1bb;
    --hero-gradient: radial-gradient(ellipse at 30% 0%, #00e59b22 0%, transparent 60%);
    --nav-hover-bg: #00e59b10; --table-hover: #00e59b08;
    --scrollbar-thumb: #1e2a38; --noise-opacity: 0.03;
    --toggle-bg: #1e2a38; --toggle-icon: #e3b341;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
  }
  [data-theme="light"] {
    --bg: #f8f6f1; --bg-surface: #ffffff; --bg-card: #ffffff;
    --bg-code: #f4f1ec; --accent: #00875a; --accent-dim: #00875a22;
    --accent-glow: #00875a0a; --text-primary: #1a1a1a;
    --text-body: #4a4a4a; --text-muted: #8a8a8a;
    --border: #e0ddd6; --border-accent: #00875a44;
    --tag-blue: #0969da; --tag-orange: #bc4c00; --tag-purple: #8250df;
    --tag-red: #cf222e; --tag-yellow: #9a6700;
    --info-bg: #00875a10; --info-text: #005a3a;
    --warn-bg: #9a670010; --warn-text: #6b4c00;
    --danger-bg: #cf222e10; --danger-text: #8c1d18;
    --hero-gradient: radial-gradient(ellipse at 30% 0%, #00875a15 0%, transparent 60%);
    --nav-hover-bg: #00875a08; --table-hover: #00875a06;
    --scrollbar-thumb: #d0cdc6; --noise-opacity: 0.015;
    --toggle-bg: #e8e5de; --toggle-icon: #00875a;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  }
  * { margin: 0; padding: 0; box-sizing: border-box; }
  html { scroll-behavior: smooth; }
  body {
    font-family: 'DM Sans', sans-serif; background: var(--bg);
    color: var(--text-body); line-height: 1.75; font-size: 16px;
    overflow-x: hidden; transition: background 0.35s, color 0.35s;
  }
  body::before {
    content: ''; position: fixed; inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='1'/%3E%3C/svg%3E");
    opacity: var(--noise-opacity); pointer-events: none; z-index: 9999;
  }
  .layout { display: grid; grid-template-columns: 280px 1fr; min-height: 100vh; }
  .sidebar {
    position: sticky; top: 0; height: 100vh; background: var(--bg-surface);
    border-right: 1px solid var(--border); padding: 32px 0;
    overflow-y: auto; scrollbar-width: thin;
    scrollbar-color: var(--scrollbar-thumb) transparent;
    display: flex; flex-direction: column;
    transition: background 0.35s, border-color 0.35s;
  }
  .sidebar-logo {
    padding: 0 24px 28px; border-bottom: 1px solid var(--border);
    margin-bottom: 20px; display: flex; align-items: center;
    justify-content: space-between;
  }
  .sidebar-logo-left h2 {
    font-family: 'JetBrains Mono', monospace; font-size: 20px;
    font-weight: 700; color: var(--text-primary);
    display: flex; align-items: center; gap: 10px;
  }
  .sidebar-logo-left h2 .icon {
    width: 32px; height: 32px; background: var(--accent);
    border-radius: 6px; display: flex; align-items: center;
    justify-content: center; color: #fff; font-weight: 700; font-size: 16px;
  }
  .sidebar-logo-left p {
    font-size: 12px; color: var(--text-muted); margin-top: 6px;
    font-family: 'JetBrains Mono', monospace;
  }
  .theme-toggle {
    width: 44px; height: 24px; border-radius: 12px;
    background: var(--toggle-bg); border: 1px solid var(--border);
    cursor: pointer; position: relative; flex-shrink: 0;
    transition: background 0.3s;
  }
  .theme-toggle::after {
    content: ''; position: absolute; top: 2px; left: 2px;
    width: 18px; height: 18px; border-radius: 50%;
    background: var(--toggle-icon);
    transition: transform 0.3s ease; box-shadow: 0 1px 3px rgba(0,0,0,0.2);
  }
  [data-theme="light"] .theme-toggle::after { transform: translateX(20px); }
  .theme-toggle .toggle-label {
    position: absolute; top: 50%; transform: translateY(-50%);
    font-size: 10px; pointer-events: none;
  }
  .theme-toggle .sun { right: 5px; opacity: 0.4; }
  .theme-toggle .moon { left: 5px; opacity: 1; }
  [data-theme="light"] .theme-toggle .sun { opacity: 1; }
  [data-theme="light"] .theme-toggle .moon { opacity: 0.4; }
  .sidebar-nav-scroll { flex: 1; overflow-y: auto; }
  .nav-group { margin-bottom: 8px; }
  .nav-group-title {
    font-family: 'JetBrains Mono', monospace; font-size: 10px;
    font-weight: 600; text-transform: uppercase; letter-spacing: 0.12em;
    color: var(--text-muted); padding: 12px 24px 6px;
  }
  .nav-link {
    display: block; padding: 8px 24px; font-size: 13.5px;
    color: var(--text-body); text-decoration: none;
    border-left: 2px solid transparent;
    font-family: 'JetBrains Mono', monospace; font-weight: 400;
    transition: color 0.2s, background 0.2s, border-color 0.2s;
  }
  .nav-link:hover {
    color: var(--accent); background: var(--nav-hover-bg);
    border-left-color: var(--accent);
  }
  .nav-link.active {
    color: var(--accent); border-left-color: var(--accent);
    background: var(--nav-hover-bg);
  }
  .sidebar-footer {
    padding: 16px 24px; border-top: 1px solid var(--border); flex-shrink: 0;
  }
  .sidebar-export-btn {
    display: flex; align-items: center; justify-content: center; gap: 8px;
    width: 100%; padding: 9px 16px; background: var(--accent-dim);
    border: 1px solid var(--border-accent); border-radius: 6px;
    color: var(--accent); font-family: 'JetBrains Mono', monospace;
    font-size: 12px; font-weight: 600; cursor: pointer;
    transition: background 0.2s, color 0.2s;
  }
  .sidebar-export-btn:hover { background: var(--accent); color: #fff; }
  .sidebar-export-btn svg { flex-shrink: 0; }
  .main { max-width: 860px; padding: 56px 64px 120px; }
  .hero { margin-bottom: 64px; position: relative; }
  .hero::before {
    content: ''; position: absolute; top: -56px; left: -64px; right: -64px;
    height: 400px; background: var(--hero-gradient); pointer-events: none;
  }
  .hero-tag {
    font-family: 'JetBrains Mono', monospace; font-size: 12px;
    font-weight: 600; color: var(--accent); text-transform: uppercase;
    letter-spacing: 0.15em; margin-bottom: 16px; position: relative;
  }
  .hero h1 {
    font-family: 'Noto Serif SC', serif; font-size: 48px;
    font-weight: 700; color: var(--text-primary); line-height: 1.2;
    margin-bottom: 20px; position: relative;
  }
  .hero p { font-size: 17px; color: var(--text-body); max-width: 600px; position: relative; }
  .hero-meta {
    margin-top: 28px; display: flex; gap: 24px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 12px; color: var(--text-muted); position: relative;
  }
  .hero-meta span { display: flex; align-items: center; gap: 6px; }
  .hero-meta .dot { width: 6px; height: 6px; border-radius: 50%; background: var(--accent); }
  .hero-actions {
    margin-top: 32px; position: relative;
    display: flex; gap: 12px; flex-wrap: wrap;
  }
  .export-btn {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 11px 28px; background: var(--accent); color: #fff;
    border: none; border-radius: 8px;
    font-family: 'JetBrains Mono', monospace; font-size: 13px;
    font-weight: 600; cursor: pointer; transition: all 0.2s;
  }
  .export-btn:hover { opacity: 0.88; transform: translateY(-1px); box-shadow: 0 6px 24px var(--accent-dim); }
  .export-btn svg { flex-shrink: 0; }
  .copy-btn {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 11px 24px; background: transparent;
    color: var(--text-body); border: 1px solid var(--border);
    border-radius: 8px; font-family: 'JetBrains Mono', monospace;
    font-size: 13px; font-weight: 500; cursor: pointer;
    transition: border-color 0.2s, color 0.2s;
  }
  .copy-btn:hover { border-color: var(--accent); color: var(--accent); }
  .copy-btn svg { flex-shrink: 0; }
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  .section:nth-child(3) { animation-delay: 0.1s; }
  .section:nth-child(4) { animation-delay: 0.15s; }
  @keyframes fadeUp { from { opacity:0; transform:translateY(16px); } to { opacity:1; transform:translateY(0); } }
  .section-anchor { display: block; position: relative; top: -80px; visibility: hidden; }
  .section-header {
    display: flex; align-items: center; gap: 14px;
    margin-bottom: 24px; padding-bottom: 16px;
    border-bottom: 1px solid var(--border);
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    font-family: 'JetBrains Mono', monospace; font-size: 13px;
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  p { margin-bottom: 16px; }
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    position: relative; margin: 20px 0 28px; border-radius: 10px;
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    background: var(--bg-code); box-shadow: var(--shadow-sm);
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  .code-header {
    display: flex; align-items: center; justify-content: space-between;
    padding: 10px 16px; background: var(--bg-surface);
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  pre {
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    font-family: 'JetBrains Mono', monospace;
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  }
  pre code { font-family: inherit; }
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  .kw  { color: var(--tag-purple); }
  .fn  { color: #d2a8ff; }
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  }
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  li { margin-bottom: 8px; padding-left: 4px; }
  li::marker { color: var(--accent); }
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    font-family: 'JetBrains Mono', monospace; font-size: 11px;
    font-weight: 700; text-transform: uppercase; letter-spacing: 0.08em;
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    background: var(--bg-surface); border: 1px solid var(--border);
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    align-items: center; justify-content: center;
  }
  .mobile-theme-btn {
    display: none; position: fixed; top: 16px; right: 16px; z-index: 1000;
    width: 40px; height: 40px; border-radius: 8px;
    background: var(--bg-surface); border: 1px solid var(--border);
    color: var(--text-primary); font-size: 18px; cursor: pointer;
    align-items: center; justify-content: center;
  }
  .sidebar-overlay {
    display: none; position: fixed; inset: 0; z-index: 998;
    background: rgba(0,0,0,0.4);
  }
  .sidebar-overlay.show { display: block; }
  .toast {
    position: fixed; bottom: 32px; right: 32px; z-index: 10000;
    padding: 14px 28px; border-radius: 10px;
    font-family: 'JetBrains Mono', monospace; font-size: 13px;
    font-weight: 600; box-shadow: var(--shadow-md);
    display: flex; align-items: center; gap: 10px;
    animation: toastIn 0.3s ease;
  }
  .toast.success { background: var(--accent); color: #fff; }
  .toast.info { background: var(--tag-blue); color: #fff; }
  @keyframes toastIn { from { transform: translateY(20px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }
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    .layout { grid-template-columns: 1fr; }
    .sidebar { position: fixed; left: -300px; top: 0; width: 280px; z-index: 999; transition: left 0.3s; }
    .sidebar.open { left: 0; }
    .mobile-toggle, .mobile-theme-btn { display: flex; }
    .main { padding: 80px 24px 80px; }
    .hero h1 { font-size: 32px; }
    .hero::before { left: -24px; right: -24px; }
  }
  ::-webkit-scrollbar { width: 6px; height: 6px; }
  ::-webkit-scrollbar-track { background: transparent; }
  ::-webkit-scrollbar-thumb { background: var(--scrollbar-thumb); border-radius: 3px; }
</style>
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      <h2><span class="icon">N</span> Nginx 教程</h2>
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    <div class="hero-tag">Open-Source Web Server</div>
    <h1>Nginx 完全教程</h1>
    <p>从零开始掌握 Nginx 的安装、配置与运维。涵盖反向代理、负载均衡、HTTPS、缓存、安全加固等核心知识，配合大量实战配置示例。</p>
    <div class="hero-meta">
      <span><span class="dot"></span> 阅读时间约 30 分钟</span>
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  <!-- 01 -->
  <div class="section" id="intro">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">01</span><h2>Nginx 简介</h2></div>
    <p><strong>Nginx</strong>（发音 "engine-x"）是一个高性能的 HTTP 和反向代理服务器，由 Igor Sysoev 于 2004 年首次发布。它以<strong>事件驱动、异步非阻塞</strong>的架构闻名，能够以极低的内存消耗处理数万并发连接。</p>
    <h3>Nginx 能做什么？</h3>
    <ul>
      <li><strong>HTTP 服务器</strong> — 高效提供静态文件服务</li>
      <li><strong>反向代理</strong> — 将请求转发给后端应用服务器</li>
      <li><strong>负载均衡</strong> — 在多台后端之间分发流量</li>
      <li><strong>SSL/TLS 终端</strong> — 处理 HTTPS 加密解密</li>
      <li><strong>API 网关</strong> — 路由、限流、鉴权</li>
      <li><strong>邮件代理</strong> — IMAP/POP3/SMTP 代理</li>
    </ul>
    <h3>Nginx vs Apache</h3>
    <div class="table-wrap"><table>
      <thead><tr><th>特性</th><th>Nginx</th><th>Apache</th></tr></thead>
      <tbody>
        <tr><td>架构模型</td><td>事件驱动 / 异步非阻塞</td><td>进程 / 线程驱动</td></tr>
        <tr><td>并发性能</td><td>极高（C10K+）</td><td>中等</td></tr>
        <tr><td>内存占用</td><td>低</td><td>相对较高</td></tr>
        <tr><td>静态文件</td><td>极快</td><td>良好</td></tr>
        <tr><td>动态内容</td><td>需借助外部（PHP-FPM等）</td><td>内置 mod_php</td></tr>
        <tr><td>配置风格</td><td>集中式、声明式</td><td>.htaccess 分散式</td></tr>
      </tbody>
    </table></div>
  </div>

  <!-- 02 -->
  <div class="section" id="install-linux">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">02</span><h2>Linux 安装与启动</h2></div>
    <h3>Ubuntu / Debian</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">bash</span></div>
    <pre><code><span class="cm"># 更新软件源并安装</span>
<span class="kw">sudo</span> apt update
<span class="kw">sudo</span> apt <span class="kw">install</span> -y nginx

<span class="cm"># 启动 &amp; 设为开机自启</span>
<span class="kw">sudo</span> systemctl start nginx
<span class="kw">sudo</span> systemctl enable nginx

<span class="cm"># 验证安装</span>
nginx -v</code></pre></div>
    <h3>CentOS / RHEL / Fedora</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">bash</span></div>
    <pre><code><span class="cm"># CentOS 7</span>
<span class="kw">sudo</span> yum install -y epel-release
<span class="kw">sudo</span> yum install -y nginx

<span class="cm"># CentOS 8+ / Fedora</span>
<span class="kw">sudo</span> dnf install -y nginx

<span class="kw">sudo</span> systemctl start nginx
<span class="kw">sudo</span> systemctl enable nginx</code></pre></div>
    <h3>macOS (Homebrew)</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">bash</span></div>
    <pre><code>brew install nginx
brew services start nginx</code></pre></div>
    <h3>Docker</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">bash</span></div>
    <pre><code>docker run -d --name nginx \
  -p <span class="nr">80</span>:<span class="nr">80</span> \
  -v /path/to/html:/usr/share/nginx/html \
  -v /path/to/nginx.conf:/etc/nginx/nginx.conf \
  nginx:stable</code></pre></div>
    <h3>常用管理命令</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">bash</span></div>
    <pre><code>nginx -t              <span class="cm"># 测试配置语法</span>
nginx -T              <span class="cm"># 测试并输出完整配置</span>
nginx -s reload       <span class="cm"># 平滑重载（不中断服务）</span>
nginx -s stop         <span class="cm"># 快速停止</span>
nginx -s quit         <span class="cm"># 优雅停止</span>
nginx -s reopen       <span class="cm"># 重新打开日志</span>
nginx -V              <span class="cm"># 查看编译参数</span></code></pre></div>
    <div class="info-box tip"><span class="label">提示</span>
      生产环境推荐使用 <code>nginx -s reload</code> 来应用配置变更，该操作是零停机的。
    </div>
  </div>

  <!-- 03 -->
  <div class="section" id="install-windows">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">03</span><h2>Windows 安装与配置</h2></div>
    <p>Nginx 官方提供 Windows 预编译包。虽然 Windows 版主要用于<strong>开发和测试</strong>，但掌握其安装方法对本地开发非常有用。</p>
    <div class="info-box warn"><span class="label">注意</span>
      Windows 版 Nginx 不支持 <code>select</code> 以外的事件模型，性能远不如 Linux 版。<strong>生产环境请使用 Linux。</strong>
    </div>
    <h3>方法一：下载官方压缩包</h3>
    <ol class="steps">
      <li><strong>下载 Nginx</strong><p>访问 <a href="https://nginx.org/en/download.html" target="_blank">nginx.org/download</a>，下载 Stable version 的 Windows zip 包。</p></li>
      <li><strong>解压到目标目录</strong><p>建议解压到 <code>C:\nginx</code>，路径中<strong>不要包含中文或空格</strong>。</p></li>
      <li><strong>启动 Nginx</strong></li>
    </ol>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">cmd / PowerShell</span></div>
    <pre><code><span class="kw">cd</span> C:\nginx
.\nginx.exe

<span class="cm"># 验证：浏览器访问 http://localhost</span>
tasklist /fi <span class="st">"imagename eq nginx.exe"</span></code></pre></div>
    <h3>Windows 管理命令</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">cmd / PowerShell</span></div>
    <pre><code><span class="kw">cd</span> C:\nginx
.\nginx.exe -t             <span class="cm"># 测试配置</span>
.\nginx.exe -s reload      <span class="cm"># 重载配置</span>
.\nginx.exe -s stop        <span class="cm"># 快速停止</span>
.\nginx.exe -s quit        <span class="cm"># 优雅停止</span></code></pre></div>
    <div class="info-box danger"><span class="label">重要</span>
      Windows 没有 <code>systemctl</code>，Nginx 不会自动作为服务运行。关闭命令行后 Nginx 仍在后台，需用 <code>nginx -s stop</code> 或任务管理器终止。
    </div>
    <h3>端口冲突排查</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">PowerShell (管理员)</span></div>
    <pre><code>netstat -ano | findstr <span class="st">":80 "</span>
iisreset /stop             <span class="cm"># 停止 IIS</span>
net stop W3SVC             <span class="cm"># 停止 WWW 服务</span></code></pre></div>
    <h3>方法二：Chocolatey</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">PowerShell (管理员)</span></div>
    <pre><code>choco install nginx -y</code></pre></div>
    <h3>方法三：Scoop</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">PowerShell</span></div>
    <pre><code>scoop bucket add main
scoop install nginx</code></pre></div>
    <h3>方法四：Docker Desktop</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">docker-compose.yml</span></div>
    <pre><code><span class="kw">version</span>: <span class="st">"3.8"</span>
<span class="kw">services</span>:
  <span class="at">nginx</span>:
    <span class="at">image</span>: nginx:stable
    <span class="at">ports</span>: [<span class="st">"80:80"</span>, <span class="st">"443:443"</span>]
    <span class="at">volumes</span>:
      - ./html:/usr/share/nginx/html
      - ./nginx.conf:/etc/nginx/nginx.conf:ro
    <span class="at">restart</span>: unless-stopped</code></pre></div>
    <h3>注册为系统服务（NSSM）</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">PowerShell (管理员)</span></div>
    <pre><code><span class="cm"># 下载: https://nssm.cc/download</span>
nssm install Nginx <span class="st">"C:\nginx\nginx.exe"</span>
nssm set Nginx AppDirectory <span class="st">"C:\nginx"</span>
nssm set Nginx Start SERVICE_AUTO_START
nssm start Nginx</code></pre></div>
    <h3>Windows 配置示例</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">C:\nginx\conf\nginx.conf</span></div>
    <pre><code><span class="kw">worker_processes</span> <span class="nr">1</span>;

<span class="kw">events</span> { <span class="kw">worker_connections</span> <span class="nr">1024</span>; }

<span class="kw">http</span> {
    <span class="kw">include</span>       mime.types;
    <span class="kw">default_type</span>  application/octet-stream;
    <span class="kw">sendfile</span>  <span class="nb">on</span>;
    <span class="kw">gzip</span>     <span class="nb">on</span>;

    <span class="kw">server</span> {
        <span class="kw">listen</span> <span class="nr">80</span>;
        <span class="kw">server_name</span> localhost;

        <span class="kw">location</span> / {
            <span class="kw">root</span> html;
            <span class="kw">index</span> index.html;
        }

        <span class="kw">location</span> /api/ {
            <span class="kw">proxy_pass</span> http://<span class="nr">127.0.0.1</span>:<span class="nr">3000</span>;
            <span class="kw">proxy_set_header</span> Host $host;
            <span class="kw">proxy_set_header</span> X-Real-IP $remote_addr;
        }
    }
    <span class="kw">include</span> conf.d/*.conf;
}</code></pre></div>
    <h3>各平台安装方式对比</h3>
    <div class="table-wrap"><table>
      <thead><tr><th>平台</th><th>推荐方式</th><th>命令</th><th>场景</th></tr></thead>
      <tbody>
        <tr><td>Ubuntu/Debian</td><td>apt</td><td><code>apt install nginx</code></td><td>生产</td></tr>
        <tr><td>CentOS/RHEL</td><td>dnf</td><td><code>dnf install nginx</code></td><td>生产</td></tr>
        <tr><td>macOS</td><td>Homebrew</td><td><code>brew install nginx</code></td><td>开发</td></tr>
        <tr><td>Windows</td><td>zip</td><td>下载解压</td><td>开发</td></tr>
        <tr><td>Windows</td><td>Chocolatey</td><td><code>choco install nginx</code></td><td>开发</td></tr>
        <tr><td>Windows</td><td>Scoop</td><td><code>scoop install nginx</code></td><td>开发</td></tr>
        <tr><td>Windows</td><td>Docker</td><td><code>docker run nginx</code></td><td>一致性</td></tr>
      </tbody>
    </table></div>
  </div>

  <!-- 04 -->
  <div class="section" id="concepts">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">04</span><h2>核心概念</h2></div>
    <h3>请求处理模型</h3>
    <p>Nginx 采用<strong>一个 Master 进程 + 多个 Worker 进程</strong>的模型。</p>
    <div class="diagram"><span class="highlight">Client Request</span>
   │
   ▼
┌──────────────────────────────┐
│       <span class="accent2">Master Process</span>         │
│   (读取配置, 管理 Worker)     │
└──────┬───────────┬───────────┘
       │           │
  ┌────▼────┐ ┌────▼────┐
  │<span class="highlight">Worker 1</span> │ │<span class="highlight">Worker 2</span> │
  │ (epoll) │ │ (epoll) │
  └────┬────┘ └────┬────┘
       │           │
  ┌────▼────┐ ┌────▼────┐
  │Backend A│ │Backend B│
  └─────────┘ └─────────┘</div>
    <h3>关键目录</h3>
    <div class="table-wrap"><table>
      <thead><tr><th>路径</th><th>Linux</th><th>Windows</th></tr></thead>
      <tbody>
        <tr><td>主配置</td><td><code>/etc/nginx/nginx.conf</code></td><td><code>C:\nginx\conf\nginx.conf</code></td></tr>
        <tr><td>附加配置</td><td><code>/etc/nginx/conf.d/</code></td><td><code>C:\nginx\conf.d\</code></td></tr>
        <tr><td>站点根</td><td><code>/var/www/</code></td><td><code>C:\nginx\html\</code></td></tr>
        <tr><td>日志</td><td><code>/var/log/nginx/</code></td><td><code>C:\nginx\logs\</code></td></tr>
        <tr><td>MIME</td><td><code>/etc/nginx/mime.types</code></td><td><code>C:\nginx\conf\mime.types</code></td></tr>
      </tbody>
    </table></div>
  </div>

  <!-- 05 -->
  <div class="section" id="structure">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">05</span><h2>配置文件结构</h2></div>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">nginx.conf</span></div>
    <pre><code><span class="kw">user</span>              nginx;
<span class="kw">worker_processes</span>  auto;
<span class="kw">error_log</span>         /var/log/nginx/error.log <span class="nb">warn</span>;
<span class="kw">pid</span>               /var/run/nginx.pid;

<span class="kw">events</span> {
    <span class="kw">worker_connections</span> <span class="nr">1024</span>;
    <span class="kw">use</span> epoll;
}

<span class="kw">http</span> {
    <span class="kw">include</span>       /etc/nginx/mime.types;
    <span class="kw">default_type</span>  application/octet-stream;
    <span class="kw">sendfile</span>    <span class="nb">on</span>;
    <span class="kw">gzip</span>        <span class="nb">on</span>;
    <span class="kw">include</span>     /etc/nginx/conf.d/*.conf;

    <span class="kw">server</span> {
        <span class="kw">listen</span>      <span class="nr">80</span>;
        <span class="kw">server_name</span> example.com;
        <span class="kw">root</span>        /var/www/example;
        <span class="kw">location</span> /      { <span class="kw">index</span> index.html; }
        <span class="kw">location</span> /api/  { <span class="kw">proxy_pass</span> http://<span class="nr">127.0.0.1</span>:<span class="nr">3000</span>; }
    }
}</code></pre></div>
    <h3>配置层次</h3>
    <div class="diagram"><span class="highlight">main</span>        ← 全局
├── <span class="accent2">events</span>    ← 事件
└── <span class="accent2">http</span>      ← HTTP
      ├── <span class="accent2">server</span>  ← 虚拟主机
      │   └── <span class="accent2">location</span> ← URL
      └── <span class="accent2">upstream</span> ← 后端组</div>
    <div class="info-box warn"><span class="label">注意</span>
      修改配置后务必先执行 <code>nginx -t</code> 测试语法。
    </div>
  </div>

  <!-- 06 -->
  <div class="section" id="virtual-host">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">06</span><h2>虚拟主机</h2></div>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">site-a.conf</span></div>
    <pre><code><span class="kw">server</span> {
    <span class="kw">listen</span> <span class="nr">80</span>;
    <span class="kw">server_name</span> site-a.com www.site-a.com;
    <span class="kw">root</span> /var/www/site-a;
    <span class="kw">location</span> / { <span class="kw">try_files</span> $uri $uri/ =<span class="nr">404</span>; }
}

<span class="cm"># 默认服务器 — 处理未匹配请求</span>
<span class="kw">server</span> {
    <span class="kw">listen</span> <span class="nr">80</span> <span class="nb">default_server</span>;
    <span class="kw">server_name</span> _;
    <span class="kw">return</span> <span class="nr">444</span>;
}</code></pre></div>
  </div>

  <!-- 07 -->
  <div class="section" id="location">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">07</span><h2>Location 路由匹配</h2></div>
    <div class="table-wrap"><table>
      <thead><tr><th>语法</th><th>类型</th><th>优先级</th></tr></thead>
      <tbody>
        <tr><td><code>= /path</code></td><td>精确匹配</td><td>最高</td></tr>
        <tr><td><code>^~ /path</code></td><td>前缀匹配</td><td>高</td></tr>
        <tr><td><code>~ pattern</code></td><td>正则（区分大小写）</td><td>中</td></tr>
        <tr><td><code>~* pattern</code></td><td>正则（不区分）</td><td>中</td></tr>
        <tr><td><code>/path</code></td><td>普通前缀</td><td>低</td></tr>
      </tbody>
    </table></div>
    <h3>实战示例</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">nginx.conf</span></div>
    <pre><code><span class="kw">location</span> = /                    { <span class="kw">proxy_pass</span> http://<span class="nr">127.0.0.1</span>:<span class="nr">3000</span>/home; }
<span class="kw">location</span> ~* \.(js|css|png|jpg)$  { <span class="kw">expires</span> <span class="nr">30d</span>; <span class="kw">access_log</span> <span class="nb">off</span>; }
<span class="kw">location</span> ^~ /api/                { <span class="kw">proxy_pass</span> http://backend; }
<span class="kw">location</span> /                       { <span class="kw">try_files</span> $uri $uri/ /index.html; }
<span class="kw">location</span> ~ /\.                    { <span class="kw">deny</span> all; }</code></pre></div>
    <div class="info-box tip"><span class="label">try_files</span>
      <code>try_files $uri $uri/ /index.html</code> — 先尝试文件 → 再尝试目录 → 都不存在返回 index.html（适合 SPA）。
    </div>
  </div>

  <!-- 08 -->
  <div class="section" id="proxy">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">08</span><h2>反向代理</h2></div>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">proxy.conf</span></div>
    <pre><code><span class="kw">server</span> {
    <span class="kw">listen</span> <span class="nr">80</span>;
    <span class="kw">server_name</span> api.example.com;
    <span class="kw">location</span> / {
        <span class="kw">proxy_pass</span>         http://<span class="nr">127.0.0.1</span>:<span class="nr">3000</span>;
        <span class="kw">proxy_set_header</span>   Host $host;
        <span class="kw">proxy_set_header</span>   X-Real-IP $remote_addr;
        <span class="kw">proxy_set_header</span>   X-Forwarded-For $proxy_add_x_forwarded_for;
        <span class="kw">proxy_set_header</span>   X-Forwarded-Proto $scheme;
        <span class="kw">proxy_connect_timeout</span> <span class="nr">60s</span>;
        <span class="kw">proxy_read_timeout</span>    <span class="nr">60s</span>;
    }
}</code></pre></div>
  </div>

  <!-- 09 -->
  <div class="section" id="static">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">09</span><h2>静态资源服务</h2></div>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">static.conf</span></div>
    <pre><code><span class="kw">server</span> {
    <span class="kw">listen</span> <span class="nr">80</span>;
    <span class="kw">root</span> /var/www/static;
    <span class="kw">sendfile</span> <span class="nb">on</span>;
    <span class="kw">gzip</span> <span class="nb">on</span>;
    <span class="kw">gzip_types</span> text/plain text/css application/javascript
               application/json image/svg+xml font/woff2;

    <span class="kw">location</span> ~* \.(js|css|png|jpg|svg|woff2)$ {
        <span class="kw">expires</span> <span class="nr">30d</span>;
        <span class="kw">add_header</span> Cache-Control <span class="st">"public, immutable"</span>;
    }
    <span class="kw">location</span> ~ /\. { <span class="kw">deny</span> all; }
}</code></pre></div>
  </div>

  <!-- 10 -->
  <div class="section" id="ssl">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">10</span><h2>HTTPS / SSL</h2></div>
    <h3>Let's Encrypt</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">bash</span></div>
    <pre><code><span class="kw">sudo</span> apt install certbot python3-certbot-nginx
<span class="kw">sudo</span> certbot --nginx -d example.com
<span class="kw">echo</span> <span class="st">"0 3 * * * certbot renew --quiet"</span> | <span class="kw">sudo</span> crontab -</code></pre></div>
    <h3>手动配置</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">ssl.conf</span></div>
    <pre><code><span class="kw">server</span> {
    <span class="kw">listen</span> <span class="nr">80</span>;
    <span class="kw">server_name</span> example.com;
    <span class="kw">return</span> <span class="nr">301</span> https://$host$request_uri;
}

<span class="kw">server</span> {
    <span class="kw">listen</span> <span class="nr">443</span> ssl http2;
    <span class="kw">server_name</span> example.com;
    <span class="kw">ssl_certificate</span>      /etc/letsencrypt/live/example.com/fullchain.pem;
    <span class="kw">ssl_certificate_key</span>  /etc/letsencrypt/live/example.com/privkey.pem;
    <span class="kw">ssl_protocols</span>        TLSv1.2 TLSv1.3;
    <span class="kw">ssl_prefer_server_ciphers</span> <span class="nb">on</span>;
    <span class="kw">add_header</span> Strict-Transport-Security <span class="st">"max-age=63072000; includeSubDomains"</span> always;
    <span class="kw">root</span> /var/www/example;
}</code></pre></div>
  </div>

  <!-- 11 -->
  <div class="section" id="loadbalance">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">11</span><h2>负载均衡</h2></div>
    <div class="table-wrap"><table>
      <thead><tr><th>算法</th><th>指令</th><th>说明</th></tr></thead>
      <tbody>
        <tr><td>轮询</td><td>—</td><td>按顺序分配</td></tr>
        <tr><td>加权轮询</td><td><code>weight=N</code></td><td>按权重分配</td></tr>
        <tr><td>IP Hash</td><td><code>ip_hash</code></td><td>同 IP 同后端</td></tr>
        <tr><td>最少连接</td><td><code>least_conn</code></td><td>最少连接优先</td></tr>
      </tbody>
    </table></div>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">upstream.conf</span></div>
    <pre><code><span class="kw">upstream</span> backend {
    <span class="kw">server</span> <span class="nr">10.0.0.1</span>:<span class="nr">8080</span> weight=<span class="nr">3</span>;
    <span class="kw">server</span> <span class="nr">10.0.0.2</span>:<span class="nr">8080</span> weight=<span class="nr">2</span>;
    <span class="kw">server</span> <span class="nr">10.0.0.3</span>:<span class="nr">8080</span> backup;
}

<span class="kw">server</span> {
    <span class="kw">listen</span> <span class="nr">80</span>;
    <span class="kw">location</span> / {
        <span class="kw">proxy_pass</span> http://backend;
        <span class="kw">proxy_next_upstream</span> error timeout http_502 http_503;
    }
}</code></pre></div>
  </div>

  <!-- 12 -->
  <div class="section" id="cache">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">12</span><h2>缓存配置</h2></div>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">cache.conf</span></div>
    <pre><code><span class="kw">proxy_cache_path</span> /var/cache/nginx
    levels=<span class="nr">1</span>:<span class="nr">2</span> keys_zone=my_cache:<span class="nr">10m</span>
    max_size=<span class="nr">1g</span> inactive=<span class="nr">60m</span> use_temp_path=off;

<span class="kw">location</span> / {
    <span class="kw">proxy_pass</span> http://backend;
    <span class="kw">proxy_cache</span> my_cache;
    <span class="kw">proxy_cache_valid</span> <span class="nr">200</span> <span class="nr">302</span> <span class="nr">10m</span>;
    <span class="kw">proxy_cache_valid</span> <span class="nr">404</span> <span class="nr">1m</span>;
    <span class="kw">add_header</span> X-Cache-Status $upstream_cache_status;
}</code></pre></div>
  </div>

  <!-- 13 -->
  <div class="section" id="rewrite">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">13</span><h2>Rewrite 规则</h2></div>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">rewrite.conf</span></div>
    <pre><code><span class="cm"># 强制 www</span>
<span class="kw">server</span> {
    <span class="kw">listen</span> <span class="nr">80</span>;
    <span class="kw">server_name</span> example.com;
    <span class="kw">return</span> <span class="nr">301</span> http://www.example.com$request_uri;
}

<span class="cm"># URL 美化</span>
<span class="kw">rewrite</span> ^/article/(\d+)$ /article.php?id=$<span class="nr">1</span> <span class="nb">last</span>;

<span class="cm"># 旧路径重定向</span>
<span class="kw">rewrite</span> ^/old-page$ /new-page <span class="nb">permanent</span>;</code></pre></div>
  </div>

  <!-- 14 -->
  <div class="section" id="websocket">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">14</span><h2>WebSocket 代理</h2></div>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">websocket.conf</span></div>
    <pre><code><span class="kw">location</span> /ws/ {
    <span class="kw">proxy_pass</span> http://ws_backend;
    <span class="kw">proxy_http_version</span> <span class="nr">1.1</span>;
    <span class="kw">proxy_set_header</span> Upgrade $http_upgrade;
    <span class="kw">proxy_set_header</span> Connection <span class="st">"upgrade"</span>;
    <span class="kw">proxy_read_timeout</span> <span class="nr">3600s</span>;
    <span class="kw">proxy_buffering</span> <span class="nb">off</span>;
}</code></pre></div>
  </div>

  <!-- 15 -->
  <div class="section" id="security">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">15</span><h2>安全加固</h2></div>
    <h3>安全响应头</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">security.conf</span></div>
    <pre><code><span class="kw">server_tokens</span> <span class="nb">off</span>;
<span class="kw">add_header</span> X-Frame-Options <span class="st">"SAMEORIGIN"</span> always;
<span class="kw">add_header</span> X-Content-Type-Options <span class="st">"nosniff"</span> always;
<span class="kw">add_header</span> X-XSS-Protection <span class="st">"1; mode=block"</span> always;
<span class="kw">add_header</span> Referrer-Policy <span class="st">"strict-origin-when-cross-origin"</span> always;</code></pre></div>
    <h3>限流</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">limit.conf</span></div>
    <pre><code><span class="kw">limit_req_zone</span> $binary_remote_addr zone=api:<span class="nr">10m</span> rate=<span class="nr">10r</span>/s;

<span class="kw">location</span> /api/ {
    <span class="kw">limit_req</span> zone=api burst=<span class="nr">20</span> nodelay;
    <span class="kw">limit_req_status</span> <span class="nr">429</span>;
    <span class="kw">proxy_pass</span> http://backend;
}</code></pre></div>
  </div>

  <!-- 16 -->
  <div class="section" id="performance">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">16</span><h2>性能优化</h2></div>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">performance.conf</span></div>
    <pre><code><span class="kw">worker_processes</span> auto;
<span class="kw">worker_rlimit_nofile</span> <span class="nr">65535</span>;

<span class="kw">events</span> {
    <span class="kw">worker_connections</span> <span class="nr">10240</span>;
    <span class="kw">multi_accept</span> <span class="nb">on</span>;
    <span class="kw">use</span> epoll;
}

<span class="kw">http</span> {
    <span class="kw">sendfile</span>    <span class="nb">on</span>;
    <span class="kw">tcp_nopush</span>  <span class="nb">on</span>;
    <span class="kw">tcp_nodelay</span> <span class="nb">on</span>;
    <span class="kw">keepalive_timeout</span>  <span class="nr">65</span>;
    <span class="kw">keepalive_requests</span> <span class="nr">1000</span>;
    <span class="kw">gzip</span> <span class="nb">on</span>;
    <span class="kw">gzip_comp_level</span> <span class="nr">4</span>;
    <span class="kw">gzip_static</span> <span class="nb">on</span>;
}</code></pre></div>
  </div>

  <!-- 17 -->
  <div class="section" id="logging">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">17</span><h2>日志与监控</h2></div>
    <h3>JSON 日志</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">nginx.conf</span></div>
    <pre><code><span class="kw">log_format</span> json_log escape=json
    <span class="st">'{"time":"$time_iso8601","addr":"$remote_addr",'</span>
    <span class="st">'"method":"$request_method","uri":"$request_uri",'</span>
    <span class="st">'"status":$status,"time_s":$request_time}'</span>;

<span class="kw">access_log</span> /var/log/nginx/access.json json_log;</code></pre></div>
    <h3>常用变量</h3>
    <div class="table-wrap"><table>
      <thead><tr><th>变量</th><th>说明</th></tr></thead>
      <tbody>
        <tr><td><code>$remote_addr</code></td><td>客户端 IP</td></tr>
        <tr><td><code>$request_uri</code></td><td>完整 URI</td></tr>
        <tr><td><code>$status</code></td><td>状态码</td></tr>
        <tr><td><code>$request_time</code></td><td>处理时间</td></tr>
        <tr><td><code>$upstream_cache_status</code></td><td>缓存状态</td></tr>
      </tbody>
    </table></div>
  </div>

  <!-- 18 -->
  <div class="section" id="faq">
    <span class="section-anchor"></span>
    <div class="section-header"><span class="section-number">18</span><h2>常见问题</h2></div>
    <h3>Q: 配置修改后不生效？</h3>
    <p>先 <code>nginx -t</code> 测试语法，再 <code>nginx -s reload</code> 重载。</p>
    <h3>Q: 502 Bad Gateway？</h3>
    <ul>
      <li>后端服务是否运行</li>
      <li><code>proxy_pass</code> 地址端口是否正确</li>
      <li>防火墙是否放行</li>
      <li>查看 error.log</li>
    </ul>
    <h3>Q: 504 Gateway Timeout？</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">nginx.conf</span></div>
    <pre><code><span class="kw">proxy_connect_timeout</span> <span class="nr">120s</span>;
<span class="kw">proxy_read_timeout</span>    <span class="nr">120s</span>;</code></pre></div>
    <h3>Q: 413 Request Entity Too Large？</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">nginx.conf</span></div>
    <pre><code><span class="kw">client_max_body_size</span> <span class="nr">100m</span>;</code></pre></div>
    <h3>Q: Windows 启动失败？</h3>
    <ul>
      <li>检查 80 端口占用：<code>netstat -ano | findstr ":80"</code></li>
      <li>运行 <code>nginx -t</code> 检查配置</li>
      <li>路径中不要有中文或空格</li>
      <li>以管理员权限运行</li>
    </ul>
    <h3>Q: CORS 跨域配置？</h3>
    <div class="code-block"><div class="code-header"><div class="dots"><span></span><span></span><span></span></div><span class="lang">cors.conf</span></div>
    <pre><code><span class="kw">location</span> /api/ {
    <span class="kw">add_header</span> Access-Control-Allow-Origin $http_origin always;
    <span class="kw">add_header</span> Access-Control-Allow-Methods <span class="st">"GET, POST, PUT, DELETE, OPTIONS"</span> always;
    <span class="kw">add_header</span> Access-Control-Allow-Headers <span class="st">"Authorization, Content-Type"</span> always;
    <span class="kw">if</span> ($request_method = OPTIONS) { <span class="kw">return</span> <span class="nr">204</span>; }
    <span class="kw">proxy_pass</span> http://backend;
}</code></pre></div>

    <div class="divider"></div>
    <div class="info-box tip"><span class="label">学习资源</span>
      <ul style="margin:8px 0 0 16px">
        <li><a href="https://nginx.org/en/docs/">Nginx 官方文档</a></li>
        <li><a href="https://github.com/nginx/nginx">Nginx GitHub</a></li>
        <li><a href="https://github.com/trimstray/nginx-admins-handbook">Nginx Admin's Handbook</a></li>
        <li><a href="https://nssm.cc/">NSSM</a></li>
      </ul>
    </div>
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