使用Nginx和tomcat配置负载均衡时同步session的方法-中存储网

2014-04-02 15:55:01 来源：itjs.cn

分别下载

tomcat http://archive.apache.org/dist/tomcat/tomcat-7/v7.0.22/bin/apache-tomcat-7.0.22.tar.gz

nginx http://nginx.org/download/nginx-1.1.14.tar.gz

准备两个虚拟机：

server1 192.168.1.112

server2 192.168.1.64

Tomcat直接解压,运行,使用默认的8080端口

tar zxvf apache-tomcat-7.0.22.tar.gz

cd apache-tomcat-7.0.22/bin

./startup.sh

访问http://192.168.1.112:8080和http://192.168.1.64:8080出现Tomcat首页即可

接下来安装nginx, nginx我就直接安装在server1上

nginx_upstream_jvm_route是一个Nginx的扩展模块，用来实现基于Cookie的SessionSticky的功能，去SVN下载最新版

svn checkout http://nginx-upstream-jvm-route.googlecode.com/svn/trunk/ /root/dev/nginx-upstream-jvm-route-read-only

解压nginx

tar zxvf nginx-1.1.14.tar.gz

cd nginx-1.1.14

运行

patch -p0 < /root/dev/nginx-upstream-jvm-route-read-only/jvm_route.patch

./configure --prefix=/etc/nginx --with-http_stub_status_module --add-module=/root/dev/nginx-upstream-jvm-route-read-only/

make

make install

在nginx安装目录下的conf/目录新建一个文件proxy.conf(/etc/nginx/conf/proxy.conf), 内容如下:

proxy_redirect off;

proxy_set_header Host $host;

proxy_set_header X-Real-IP $remote_addr;

proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

client_max_body_size 10m;

client_body_buffer_size 128k;

proxy_connect_timeout 90;

proxy_send_timeout 90;

proxy_read_timeout 90;

proxy_buffer_size 4k;

proxy_buffers 4 32k;

proxy_busy_buffers_size 64k;

proxy_temp_file_write_size 64k;

修改nginx配置文件/etc/nginx/conf/nginx.conf

完整配置如下

http {

include mime.types;

#反向代理配置

include proxy.conf;

default_type application/octet-stream;

sendfile on;

keepalive_timeout 65;

upstream server1{

server 192.168.1.112:8080 srun_id=tomcat1;

server 192.168.1.64:8080 srun_id=tomcat2;

jvm_route $cookie_JSESSIONID|sessionid reverse;

}

server {

listen 80;

server_name localhost;

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

location ~ ^/NginxStatus/ {

stub_status on; #Nginx 状态监控配置

access_log off;

}

location ~ ^/(WEB-INF)/ {

deny all;

}

location / {

root html;

index index.html index.htm;

proxy_pass http://server1;

}

location /doc {

root /usr/share;

autoindex on;

allow 127.0.0.1;

deny all;

}

location /images {

root /usr/share;

autoindex on;

}

具体配置说明请参考《轻量级WEB服务器Nginx》

然后运行nginx

访问http://192.168.1.112/NginxStatus,可以看到nginx状态

然后修改tomcat配置文件, 打开apache-tomcat-7.0.22/conf/server.xml, 找到最下面的<Engine name="Catalina" defaultHost="localhost">节点, 修改为

server1

并插入如下配置

<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"

channelSendOptions="8">

<Manager className="org.apache.catalina.ha.session.DeltaManager"

expireSessionsOnShutdown="false"

notifyListenersOnReplication="true"/>

<Membership className="org.apache.catalina.tribes.membership.McastService"

address="224.0.0.4"

port="45564"

frequency="500"

dropTime="3000"/>

<Receiver className="org.apache.catalina.tribes.transport.nio.NioReceiver"

address="192.168.1.112"

port="4000"

autoBind="100"

selectorTimeout="5000"

maxThreads="6"/>

</Sender>

</Channel>

<Valve className="org.apache.catalina.ha.tcp.ReplicationValve"

filter=""/>

</Cluster>

server2

...

<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"

channelSendOptions="8">

<Manager className="org.apache.catalina.ha.session.DeltaManager"

expireSessionsOnShutdown="false"

notifyListenersOnReplication="true"/>

<Membership className="org.apache.catalina.tribes.membership.McastService"

address="224.0.0.4"

port="45564"

frequency="500"

dropTime="3000"/>

<Receiver className="org.apache.catalina.tribes.transport.nio.NioReceiver"

address="192.168.1.64"

port="4000"

autoBind="100"

selectorTimeout="5000"

maxThreads="6"/>

</Sender>

</Channel>

<Valve className="org.apache.catalina.ha.tcp.ReplicationValve"

filter=""/>

</Cluster>

...

jvmRoute="tomcat1"和nginx配置upstream中的srun_id对应

membership中的address＝224.0.0.4为组播IP，集群中的tomcat通信之用

receiver中的address设为本机IP，或auto，如果多个Tomcat在同一台电脑上，则要保证port端口不重复

在两个tomcat的webapps目录下分别新建一个项目test,

/test

/test/index.jsp

/test/WEB-INF/

/test/WEB-INF/web.xml

index.jsp内容

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<title>Insert title here</title>

</head>

<body>

<%=session.getId() %><br>

String msg = (String)session.getAttribute("msg");

if(null == msg){

session.setAttribute("msg", "Hello!");

}else{

session.setAttribute("msg", msg + 0);

}

<%=session.getAttribute("msg") %>

</body>

</html>

web.xml<?xml version="1.0" encoding="UTF-8"?>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

注意上面的distributable节点，表示该应用是在集群环境下的。

重启tomcat后在两台机子上访问http://192.168.1.112/test

从SessionId后面带的服务器名可以看到负载均衡的效果。

然后将server1上的tomcat停掉，再刷新页面，可以看到原来访问server1的页面成功地切换到了server2，而sessionId没有变，session中的msg也和原来一样。

继续阅读