简要说明：使用nginx做负载均衡；memcache做session共享

1.软件版本

nginx-1.7.3

memcached-1.4.22

2.nginx搭建负载均衡配置

编辑nginx/conf/nginx.conf 配置文件

添加负载均衡设置

upstream localhost{

server localhost:8082;

server localhost:8083;

}

添加80端口的虚拟目录，配置转发代理

1. server {
2. listen 80;
3. server_name localhost;
4. index index.html index.htm index.jsp;#Default Page
5. root /home/www/web/ROOT;#WEB LIB DIRECTRY
6.  
7. #charset koi8-r;
8.  
9. #access_log logs/host.access.log main;
10.  
11. #Set JSP Proxy
12. location /
13. {
14. proxy_set_header Host $host;
15. proxy_set_header X-Real-IP $remote_addr;
16. proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
17. proxy_pass http://localhost;
18. }
19. }

到这一步就可以实现用nginx+tomcat的负载均衡了。。

均衡后还不够，还需要对session进行处理，接下来安装好memcache.并启动

4.修改tomcat/conf/context.xml文件，添加下列代码

1. <Manager className="de.javakaffee.web.msm.MemcachedBackupSessionManager"
2. memcachedNodes="n1:127.0.0.1:11211"
3. sticky="false"
4. lockingMode="auto"
5. sessionBackupAsync="false"
6. requestUriIgnorePattern=".*\.(ico|png|gif|jpg|css|js)$"
7. sessionBackupTimeout="1000" transcoderFactoryClass="de.javakaffee.web.msm.serializer.kryo.KryoTranscoderFactory"
8. />

到此session已处理完毕；

如果配置正确。则可以看到启动的日志里面会有如下信息：

Mar 09, 2015 11:38:47 PM de.javakaffee.web.msm.MemcachedSessionService startInternal

INFO:  starts initialization... (configured nodes definition n1:10.211.55.6:11211, failover nodes null)

Mar 09, 2015 11:38:47 PM de.javakaffee.web.msm.RequestTrackingHostValve <init>

INFO: Setting ignorePattern to .*\.(ico|png|gif|jpg|css|js)$

Mar 09, 2015 11:38:47 PM de.javakaffee.web.msm.MemcachedSessionService setLockingMode

INFO: Setting lockingMode to AUTO

Mar 09, 2015 11:38:47 PM de.javakaffee.web.msm.MemcachedSessionService createTranscoderFactory

INFO: Creating transcoder factory de.javakaffee.web.msm.serializer.kryo.KryoTranscoderFactory

6.测试session的jsp文件

1. <%@ page language="java" import="java.util.*" pageEncoding="utf-8" %>
2. <%
3. HttpSession sess = request.getSession(false);
4. %>
5. <br/> session is : <%=sess.getId() %><br/>
6. <%
7. String name = request.getParameter("name");
8. if(name!=null && name.length()>0){
9. String value = request.getParameter("value");
10. sess.setAttribute(name,value);
11. TestTask.infos.add("name="+name+",value = "+value);
12. }
13. %>
14. <b>Session List:</b><br/>
15. <table >
16. <tr>
17. <td>name</td><td>value</td>
18. </tr>
19. <%
20. Enumeration<String> names=sess.getAttributeNames();
21. while(names.hasMoreElements()){
22. String sname=names.nextElement();
23. String value=sess.getAttribute(sname).toString();
24. %>
25. <tr>
26. <td><%= sname %></td><td><%=value %></td>
27. </tr>
28. <%
29. }
30. %>
31. </table>
32. <br />
33.