Apache/Nginx 反向代理 Tomcat 負載均衡完整配置實戰：單文件與多文件模式對比

Apache/Nginx 反向代理 Tomcat 負載均衡完整配置實戰：單文件與多文件模式對比

Web 架構中，Apache/Nginx 作為反向代理層分發流量至後端 Tomcat 集群是經典模式。本文提供 Apache mod_proxy_balancer 與 Nginx upstream 兩套完整配置，對比單文件與多文件模塊化配置優劣，含健康檢查、會話保持、靜態資源分離、啟動腳本等生產級細節。

一、 Apache 配置（基於 mod_proxy_balancer）

1. 安裝與模塊啟用

# 源碼編譯
./configure --prefix=/usr/local/apache --enable-proxy --enable-proxy-balancer --enable-proxy-http
make && make install

# YUM 安裝
yum install httpd mod_ssl
# 確認模塊載入
httpd -M | grep proxy

2. 虛擬主機負載均衡配置

# /etc/httpd/conf.d/tomcat_balancer.conf
Listen 8051

    ServerAdmin admin@example.com
    ServerName lb.example.com
    ErrorLog "/var/log/httpd/tomcat_balancer_error.log"
    CustomLog "/var/log/httpd/tomcat_balancer_access.log" common

    # 負載均衡核心配置
    ProxyPass / balancer://tomcat_cluster/ stickysession=JSESSIONID|jsessionid nofailover=On lbmethod=byrequests timeout=5 maxattempts=3
    ProxyPassReverse / balancer://tomcat_cluster/
    ProxyRequests Off
    ProxyPreserveHost On

    
        # BalancerMember ajp://192.168.1.10:8009 route=tomcat_a
        BalancerMember https://192.168.1.10:8080/App route=tomcat_a
        # BalancerMember ajp://192.168.1.11:8010 route=tomcat_b
        BalancerMember https://192.168.1.11:8081/App route=tomcat_b
    

關鍵參數：

• stickysession=JSESSIONID|jsessionid：會話保持，支持 Cookie 和 URL 重寫
• nofailover=On：會話節點掛掉返回 503，不重定向到其他節點（避免會話丟失）
• lbmethod=byrequests：請求計數分發（默認），可選 bytraffic/bybusyness
• route=tomcat_a：對應 Tomcat server.xml jvmRoute="tomcat_a"

3. Tomcat 會話保持配置

  
  ...

二、 Nginx 配置（基於 upstream）

1. 源碼編譯安裝

groupadd nginx && useradd -g nginx -s /sbin/nologin nginx
yum install -y make zlib-devel openssl-devel pcre-devel
tar zxvf nginx-1.18.0.tar.gz && cd nginx-1.18.0
./configure --prefix=/usr/local/nginx \
  --with-http_ssl_module --with-http_gzip_static_module --with-http_stub_status_module \
  --with-http_realip_module --with-stream
make && make install

2. 模式一：單文件配置

# /usr/local/nginx/conf/nginx.conf
user nginx;
worker_processes auto;
error_log logs/error.log warn;
pid logs/nginx.pid;

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

http {
    include mime.types;
    default_type application/octet-stream;
    
    # 性能優化
    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    client_max_body_size 100m;
    
    # Gzip
    gzip on;
    gzip_min_length 1k;
    gzip_comp_level 2;
    gzip_types text/plain application/javascript text/css application/xml;
    
    # 上游定義
    upstream app_cluster {
        server 192.168.1.10:8080 weight=1 max_fails=2 fail_timeout=30s;
        server 192.168.1.11:8081 weight=1 max_fails=2 fail_timeout=30s;
        # keepalive 32;  # 長連接池
    }
    
    upstream admin_cluster {
        server 192.168.1.10:8080 weight=1 max_fails=2 fail_timeout=30s;
        server 192.168.1.11:8081 weight=1 max_fails=2 fail_timeout=30s;
    }
    
    server {
        listen 80;
        server_name localhost;
        
        location /App {
            proxy_pass https://app_cluster;
            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_next_upstream error timeout http_500 http_502 http_503 http_504;
            proxy_connect_timeout 5s;
            proxy_read_timeout 60s;
        }
        
        location /Admin {
            proxy_pass https://admin_cluster;
            # 同樣 proxy_set_header...
        }
    }
}

3. 模式二：多文件模塊化配置（推薦生產）

# 目錄結構
/usr/local/nginx/conf/
├── nginx.conf          # 主配置
├── conf.d/
│   ├── gzip.conf       # 壓縮配置
│   ├── proxy.conf      # 代理通用參數
│   ├── upstream.conf   # 上游定義
│   └── vhosts/
│       ├── app.conf    # 業務虛擬主機
│       └── admin.conf  # 管理虛擬主機

nginx.conf：

user nginx;
worker_processes auto;
include conf.d/proxy.conf;
include conf.d/gzip.conf;
include conf.d/upstream.conf;
include conf.d/vhosts/*.conf;

conf.d/upstream.conf：

upstream app_cluster {
    server 192.168.1.10:8080 max_fails=1 fail_timeout=60s;
    server 192.168.1.11:8081 max_fails=1 fail_timeout=60s;
    keepalive 64;
}
upstream admin_cluster {
    server 192.168.1.10:8080 max_fails=1 fail_timeout=60s;
    server 192.168.1.11:8081 max_fails=1 fail_timeout=60s;
}

conf.d/proxy.conf：

proxy_connect_timeout 5s;
proxy_read_timeout 60s;
proxy_send_timeout 10s;
proxy_buffer_size 64k;
proxy_buffers 8 64k;
proxy_busy_buffers_size 128k;
proxy_temp_file_write_size 256k;
proxy_next_upstream error timeout http_500 http_502 http_503 http_504;
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_http_version 1.1;
proxy_set_header Connection "";

conf.d/vhosts/app.conf：

server {
    listen 80;
    server_name app.example.com;
    
    location / {
        proxy_pass https://app_cluster;
    }
    
    # 靜態資源直接由 Nginx 服務
    location ~* \.(jpg|jpeg|png|gif|ico|css|js|woff|woff2)$ {
        root /data/www/app;
        expires 30d;
        add_header Cache-Control "public";
    }
}

4. Nginx 系統服務註冊

# /etc/init.d/nginx
#!/bin/bash
# chkconfig: 345 99 20
PROG="/usr/local/nginx/sbin/nginx"
PIDF="/usr/local/nginx/logs/nginx.pid"
case "$1" in
    start) $PROG; echo "Nginx started." ;;
    stop) kill -s QUIT $(cat $PIDF); echo "Nginx stopped." ;;
    restart) $0 stop; $0 start ;;
    reload) kill -s HUP $(cat $PIDF); echo "Nginx reloaded." ;;
    *) echo "Usage: $0 {start|stop|restart|reload}"; exit 1 ;;
esac

chmod +x /etc/init.d/nginx
chkconfig --add nginx
chkconfig --level 2345 nginx on

三、 驗證與測試

1. 啟動兩台 Tomcat（8080/App、8081/App），部署測試頁 test.jsp 輸出節點標識
2. 訪問 https://lb.example.com:8051/App/test.jsp (Apache) 或 https://app.example.com/App/test.jsp (Nginx)
3. 連續刷新，觀察輸出在 tomcat_a / tomcat_b 間切換 → 負載均衡生效
4. 關閉一台 Tomcat，驗證流量自動切換、會話保持（Apache nofailover=On 會報 503，Nginx 默認切換）

四、 Apache vs Nginx 選型建議

五、 總結

Apache mod_proxy_balancer 會話保持成熟，適合傳統 Java 應用；Nginx upstream 配合模塊化配置、靜態資源分離、長連接池，是現代高並發架構首選。生產環境建議：Nginx 做七層網關 + 靜態分離 + 限流熔斷，Tomcat 專注業務邏輯。配置納入版本控制、變更走發布流程、監控覆蓋上游健康狀態，構建可觀測、可演進的負載均衡層。