Nginx 配置指南

基本架构

Nginx 采用事件驱动的异步架构，以 master 进程管理多个 worker 进程。

Nginx
├── master process (配置管理、worker 管理)
├── worker process 1 (处理请求)
├── worker process 2 (处理请求)
└── worker process N (处理请求)

全局配置

# /etc/nginx/nginx.conf
user nginx;
worker_processes auto;          # 自动匹配 CPU 核心数
error_log /var/log/nginx/error.log warn;
pid /var/run/nginx.pid;

events {
    worker_connections 1024;    # 每个 worker 最大连接数
    multi_accept on;            # 一次接受所有新连接
    use epoll;                  # Linux 最优事件模型
}

http {
    include /etc/nginx/mime.types;
    default_type application/octet-stream;

    sendfile on;
    tcp_nopush on;              # 优化数据包发送
    tcp_nodelay on;
    keepalive_timeout 65;

    # Gzip 压缩
    gzip on;
    gzip_types text/plain text/css application/json application/javascript;
    gzip_min_length 1000;
    gzip_vary on;

    include /etc/nginx/conf.d/*.conf;
}

静态资源服务器

server {
    listen 80;
    server_name static.example.com;
    root /var/www/static;

    # 文件缓存
    location ~* \.(jpg|jpeg|png|gif|ico|css|js)$ {
        expires 30d;
        add_header Cache-Control "public, immutable";
        access_log off;
    }

    # 禁止访问隐藏文件
    location ~ /\. {
        deny all;
        access_log off;
        log_not_found off;
    }
}

反向代理

server {
    listen 80;
    server_name api.example.com;

    location / {
        proxy_pass http://backend:8080;
        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;

        # 超时配置
        proxy_connect_timeout 30s;
        proxy_read_timeout 60s;
        proxy_send_timeout 30s;

        # 缓冲配置
        proxy_buffering on;
        proxy_buffer_size 4k;
        proxy_buffers 8 4k;
        proxy_busy_buffers_size 8k;
    }

    # WebSocket 支持
    location /ws {
        proxy_pass http://ws-backend:9000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header Host $host;
        proxy_read_timeout 86400s;
    }
}

负载均衡

upstream backend {
    # 轮询（默认）
    server 10.0.0.1:8080 weight=3;     # 权重为 3
    server 10.0.0.2:8080 weight=2;
    server 10.0.0.3:8080 backup;       # 备用服务器

    # 最少连接
    # least_conn;

    # IP 哈希（保持会话）
    # ip_hash;

    keepalive 32;                       # 保持连接池
}

server {
    listen 80;
    server_name app.example.com;

    location / {
        proxy_pass http://backend;
        proxy_http_version 1.1;
        proxy_set_header Connection "";
    }
}

HTTPS 配置

server {
    listen 443 ssl http2;
    server_name example.com;

    # 证书路径
    ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;

    # 安全配置
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256;
    ssl_prefer_server_ciphers on;
    ssl_session_cache shared:SSL:10m;
    ssl_session_timeout 10m;

    # HSTS
    add_header Strict-Transport-Security "max-age=63072000" always;

    # 其他安全头
    add_header X-Frame-Options SAMEORIGIN;
    add_header X-Content-Type-Options nosniff;
    add_header X-XSS-Protection "1; mode=block";
}

# HTTP 自动跳转 HTTPS
server {
    listen 80;
    server_name example.com;
    return 301 https://$server_name$request_uri;
}

限流配置

# 定义限流区域
limit_req_zone $binary_remote_addr zone=api_limit:10m rate=10r/s;
limit_conn_zone $binary_remote_addr zone=conn_limit:10m;

server {
    location /api/ {
        # 请求频率限制：每秒最多 10 个请求，允许突发 20 个
        limit_req zone=api_limit burst=20 nodelay;

        # 并发连接限制：每个 IP 最多 5 个连接
        limit_conn conn_limit 5;

        # 超出限制时的响应
        limit_req_status 429;

        proxy_pass http://backend;
    }
}

访问控制

server {
    # IP 白名单
    location /admin/ {
        allow 10.0.0.0/8;
        allow 192.168.0.0/16;
        deny all;
        proxy_pass http://admin-backend;
    }

    # 基本认证
    location /private/ {
        auth_basic "Restricted Access";
        auth_basic_user_file /etc/nginx/.htpasswd;
        proxy_pass http://backend;
    }
}

日志配置

# 自定义日志格式
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
                '$status $body_bytes_sent "$http_referer" '
                '"$http_user_agent" "$http_x_forwarded_for" '
                'rt=$request_time ut=$upstream_response_time';

# 详细的 API 日志
log_format api '$remote_addr | $time_local | $request_method $uri '
               '$status | $body_bytes_sent | $request_time';

server {
    access_log /var/log/nginx/access.log main buffer=32k flush=5s;
    error_log /var/log/nginx/error.log warn;

    location /api/ {
        access_log /var/log/nginx/api.log api;
        proxy_pass http://backend;
    }
}

性能调优

# 系统层面
worker_processes auto;
worker_rlimit_nofile 65535;

events {
    use epoll;
    worker_connections 65535;
    multi_accept on;
}

http {
    # 文件缓存
    open_file_cache max=2000 inactive=20s;
    open_file_cache_valid 60s;
    open_file_cache_min_uses 3;
    open_file_cache_errors off;

    # 代理缓冲
    proxy_buffers 16 16k;
    proxy_buffer_size 32k;
    proxy_busy_buffers_size 64k;

    # 超时
    client_body_timeout 10s;
    client_header_timeout 10s;
    send_timeout 10s;
}

总结

Nginx 是一个功能强大、性能卓越的 Web 服务器和反向代理。掌握其核心配置（静态文件、反向代理、负载均衡、HTTPS、限流、访问控制）是运维工程师的基本功。配置时注意安全性和性能的平衡，使用安全头保护用户，通过缓存和压缩优化性能。