# Ubuntu/Debian:
sudo apt update
sudo apt install nginx

# CentOS/RHEL:
sudo yum install epel-release
sudo yum install nginx

# macOS (使用Homebrew):
brew install nginx

# 启动Nginx
sudo systemctl start nginx

# 停止Nginx
sudo systemctl stop nginx

# 重启Nginx
sudo systemctl restart nginx

# 重新加载配置（不中断服务）
sudo systemctl reload nginx

# 设置开机启动
sudo systemctl enable nginx

# 检查配置语法
sudo nginx -t

/etc/nginx/
├── nginx.conf          # 主配置文件
├── sites-available/    # 可用站点配置
├── sites-enabled/      # 已启用站点配置（符号链接）
├── conf.d/             # 额外配置文件
└── modules-available/  # 模块配置

# 全局块：影响Nginx整体运行的配置
user www-data;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;

# Events块：影响Nginx与用户的网络连接
events {
    worker_connections 1024;
    use epoll;
}

# HTTP块：服务器相关配置
http {
    include /etc/nginx/mime.types;
    default_type application/octet-stream;
    
    # 服务器块（虚拟主机）
    server {
        listen 80;
        server_name example.com;
        
        # 位置块：URL匹配和响应处理
        location / {
            root /var/www/html;
            index index.html;
        }
    }
}

server {
    listen 80;
    server_name www.example.com;
    root /var/www/example;
    index index.html index.htm;
    
    location / {
        try_files $uri$uri/ =404;
    }
    
    # 静态资源缓存
    location ~* \.(jpg|jpeg|png|gif|ico|css|js)$ {
        expires 30d;
        add_header Cache-Control "public, immutable";
    }
}

server {
    listen 80;
    server_name api.example.com;
    
    location / {
        proxy_pass http://localhost: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;
        
        # 超时设置
        proxy_connect_timeout 60s;
        proxy_send_timeout 60s;
        proxy_read_timeout 60s;
    }
}

http {
    upstream backend {
        least_conn;  # 最少连接算法
        server backend1.example.com weight=3;
        server backend2.example.com;
        server backend3.example.com backup;
    }
    
    server {
        listen 80;
        
        location / {
            proxy_pass http://backend;
        }
    }
}

server {
    listen 443 ssl http2;
    server_name example.com;
    
    ssl_certificate /etc/ssl/certs/example.com.crt;
    ssl_certificate_key /etc/ssl/private/example.com.key;
    
    # 增强安全性
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers ECDHE-RSA-AES256-GCM-SHA512:DHE-RSA-AES256-GCM-SHA512;
    ssl_prefer_server_ciphers off;
    
    # HSTS
    add_header Strict-Transport-Security "max-age=63072000" always;
    
    location / {
        root /var/www/html;
    }
}

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

location /admin {
    # 基于IP的访问控制
    allow 192.168.1.0/24;
    allow 10.0.0.1;
    deny all;
    
    # 基本认证
    auth_basic "Restricted Area";
    auth_basic_user_file /etc/nginx/.htpasswd;
}

http {
    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;
    
    # 按日期分割日志
    map $time_iso8601$logdate {
        '~^(?<ymd>\d{4}-\d{2}-\d{2})'$ymd;
        default 'nodate';
    }
    access_log /var/log/nginx/access-$logdate.log main;
}

http {
    # 限制请求频率
    limit_req_zone $binary_remote_addr zone=one:10m rate=10r/s;
    
    # 限制连接数
    limit_conn_zone $binary_remote_addr zone=addr:10m;
    
    server {
        location /api/ {
            limit_req zone=one burst=20;
            limit_conn addr 10;
        }
    }
}

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

location /ws/ {
http {
    geo $blocked_country {
        default 0;
        # 阻止特定国家访问
        CN 1;
        RU 1;
    }
    
    server {
        if ($blocked_country = 1) {
            return 403;
        }
    }
}

events {
    worker_connections 4096;
    multi_accept on;
    use epoll;
}

http {
    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    keepalive_requests 100;
    
    # 开启Gzip压缩
    gzip on;
    gzip_comp_level 5;
    gzip_min_length 256;
    gzip_types text/plain text/css application/json application/javascript;
}

http {
    client_body_buffer_size 10K;
    client_header_buffer_size 1k;
    client_max_body_size 8m;
    large_client_header_buffers 2 1k;
    
    proxy_buffers 16 32k;
    proxy_buffer_size 64k;
    proxy_busy_buffers_size 128k;
}

# 检查配置语法
nginx -t

# 查看Nginx版本和编译参数
nginx -V

# 实时查看访问日志
tail -f /var/log/nginx/access.log

# 查看错误日志
tail -f /var/log/nginx/error.log

# 检查端口监听
sudo netstat -tulpn | grep nginx

# 检查运行用户
ps aux | grep nginx

# 修复权限
sudo chown -R www-data:www-data /var/www
sudo chmod -R 755 /var/www