一、环境准备
时间同步(同步后确认各服务器时间是否一致，不一致需要修改一下时区)
关闭防火墙
软件包和jar包链接：https://pan.baidu.com/s/1sl9Nob7
二、安装配置nginx和memcached
Nginx和memcached使用yum安装即可，下面是nginx配置文件内容
user nginx;
worker_processes 1;
events {
worker_connections 1024;
}
http {
include mime.types;
default_type application/octet-stream;
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
sendfile on;
tcp_nopush on;
keepalive_timeout 65;
gzip on;
upstream tomcat-web {
server 192.168.0.14:8080;
server 192.168.0.15:8080;
}
server {
listen 80;
server_name www.tomcat.com;
location / {
root html;
index index.html index.htm index.jsp;
}
location ~* \.(jsp|do)$ {
proxy_pass http://tomcat-web;
proxy_redirect off;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_next_upstream error timeout invalid_header http_500 http_502 http_503 http_504;
}
location /nginx_status {
stub_status on;
access_log off;
allow 192.168.0.0/24;
deny all;
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
}
}nginx.conf
分别启动nginx和memcached
三、安装配置tomcat
安装步骤忽略
下载jar包至各tomcat节点的tomcat安装目录下的lib目录中
分别在两个tomcat上的某host上定义一个用于测试的context容器，并在其中创建一个会话管理器，如下所示：
[root@tomcat-server-1 ~]# vim /usr/local/tomcat/conf/server.xml
<Host name="localhost" appBase="webapps"
unpackWARs="true" autoDeploy="true">
<Context path="/test" docBase="/usr/local/tomcat/webapps/test" reloadable="true">
<Manager className="de.javakaffee.web.msm.MemcachedBackupSessionManager"
memcachedNodes="n1:192.168.0.12:11211,n2:192.168.0.13:11211" #n1代表memcached的名称，后面为具体的ip地址
failoverNodes="n1"
requestUriIgnorePattern=".*\.(ico|png|gif|jpg|css|js)$"
transcoderFactoryClass="de.javakaffee.web.msm.serializer.javolution.JavolutionTranscoderFactory"
/>
</Context>
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
prefix="localhost_access_log" suffix=".txt"
pattern="%h %l %u %t "%r" %s %b" />
</Host>提供测试页面
tomcat-server-1
[root@tomcat-server-1 lib]# mkdir -pv /usr/local/tomcat/webapps/test/WEB-INF/{classes,lib}
[root@tomcat-server-1 lib]# vim /usr/local/tomcat/webapps/test/index.jsp
<%@ page language="java" %>
<html>
<head><title>TomcatA</title></head>
<body>
<h1><font color="red">TomcatA</font></h1>
<table align="centre" border="1">
<tr>
<td>Session ID</td>
<% session.setAttribute("tomcat","tomcat"); %>
<td><%= session.getId() %></td>
</tr>
<tr>
<td>Created on</td>
<td><%= session.getCreationTime() %></td>
</tr>
</table>
</body>
</html>tomcat-server-2
[root@tomcat-server-2 lib]# mkdir -pv /usr/local/tomcat/webapps/test/WEB-INF/{classes,lib}
[root@tomcat-server-2 lib]# vim /usr/local/tomcat/webapps/test/index.jsp
<%@ page language="java" %>
<html>
<head><title>TomcatB</title></head>
<body>
<h1><font color="blue">TomcatB</font></h1>
<table align="centre" border="1">
<tr>
<td>Session ID</td>
<% session.setAttribute("tomcat","tomcat"); %>
<td><%= session.getId() %></td>
</tr>
<tr>
<td>Created on</td>
<td><%= session.getCreationTime() %></td>
</tr>
</table>
</body>
</html>重启两台tomcat，并用浏览器进行访问
测试结果，在浏览器中访问http://www.tomcat.com/test/index.jsp，结果如上所示，其session ID在负载均衡环境中保持不变。
"一劳永逸" 的话，有是有的，而 "一劳永逸" 的事却极少