Nginx配置：Web服务器运维

Nginx简介

Nginx是一个高性能的HTTP和反向代理服务器，以高并发、低内存消耗著称，广泛用于Web服务器、反向代理和负载均衡。

安装与基本配置

# Ubuntu/Debian
sudo apt update
sudo apt install nginx

# CentOS/RHEL
sudo yum install nginx

# 启动服务
sudo systemctl start nginx
sudo systemctl enable nginx

# 验证配置
sudo nginx -t

核心配置

主配置文件

# /etc/nginx/nginx.conf
user www-data;
worker_processes auto;
pid /run/nginx.pid;

events {
    worker_connections 1024;
    multi_accept on;
}

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

    # 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"';

    access_log /var/log/nginx/access.log main;
    error_log /var/log/nginx/error.log warn;

    # 性能优化
    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    types_hash_max_size 2048;

    # Gzip压缩
    gzip on;
    gzip_vary on;
    gzip_proxied any;
    gzip_comp_level 6;
    gzip_types text/plain text/css application/json application/javascript text/xml application/xml;

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

虚拟主机配置

# /etc/nginx/conf.d/example.conf
server {
    listen 80;
    server_name example.com www.example.com;
    root /var/www/example;
    index index.html index.htm;

    # 静态文件缓存
    location ~* \.(jpg|jpeg|png|gif|ico|css|js)$ {
        expires 30d;
        add_header Cache-Control "public, no-transform";
    }

    # 应用代理
    location / {
        try_files $uri $uri/ /index.html;
    }

    # API代理
    location /api/ {
        proxy_pass http://127.0.0.1:8080;
        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;
    }
}

反向代理

基本代理

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;
}

WebSocket代理

location /ws {
    proxy_pass http://backend:8080;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
    proxy_set_header Host $host;
}

代理缓冲

location /api/ {
    proxy_pass http://backend:8080;
    proxy_buffering on;
    proxy_buffer_size 4k;
    proxy_buffers 8 4k;
    proxy_busy_buffers_size 8k;
}

负载均衡

配置负载均衡

# upstream配置
upstream backend {
    least_conn;
    server backend1:8080 weight=3;
    server backend2:8080 weight=2;
    server backend3:8080 backup;
}

server {
    listen 80;
    location / {
        proxy_pass http://backend;
    }
}

负载均衡算法

# 轮询（默认）
upstream backend {
    server backend1:8080;
    server backend2:8080;
}

# 加权轮询
upstream backend {
    server backend1:8080 weight=3;
    server backend2:8080 weight=2;
}

# IP哈希
upstream backend {
    ip_hash;
    server backend1:8080;
    server backend2:8080;
}

# 最少连接
upstream backend {
    least_conn;
    server backend1:8080;
    server backend2:8080;
}

HTTPS配置

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

    ssl_certificate /etc/nginx/ssl/example.com.crt;
    ssl_certificate_key /etc/nginx/ssl/example.com.key;
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers HIGH:!aNULL:!MD5;
    ssl_prefer_server_ciphers on;

    # HSTS
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
}

# HTTP重定向
server {
    listen 80;
    server_name example.com;
    return 301 https://$server_name$request_uri;
}

安全配置

# 隐藏版本号
server_tokens off;

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

# 限制请求大小
client_max_body_size 10M;

# 限制连接数
limit_conn_zone $binary_remote_addr zone=conn_limit:10m;
limit_req_zone $binary_remote_addr zone=req_limit:10m rate=10r/s;

location / {
    limit_conn conn_limit 50;
    limit_req zone=req_limit burst=20 nodelay;
}

性能优化

# 开启gzip
gzip on;
gzip_min_length 1024;
gzip_types text/plain text/css application/json application/javascript;

# 缓存配置
proxy_cache_path /var/cache/nginx levels=1:2 keys_zone=my_cache:10m max_size=10g inactive=60m;

location / {
    proxy_cache my_cache;
    proxy_cache_valid 200 302 10m;
    proxy_cache_valid 404 1m;
    proxy_cache_key $scheme$host$request_uri;
}

常用命令

# 测试配置
sudo nginx -t

# 重新加载配置
sudo nginx -s reload

# 停止服务
sudo nginx -s stop

# 查看进程
ps aux | grep nginx

# 查看连接状态
curl http://localhost/nginx_status

总结

Nginx是现代Web架构的核心组件。掌握配置技巧，可以构建高性能、高可用的Web服务。