實驗系統：CentOS 6.6_x86_64
實驗前提：提前準備好編譯環境，防火墻和selinux都關閉
實驗說明：本實驗共有2臺主機，ip分配如拓撲
實驗軟件：jdk-8u60-linux-x64 apache-tomcat-8.0.24 tomcat-connectors-1.2.41 httpd-2.2.15 httpd-devel-2.2.15
實驗拓撲：
一、兩臺機器安裝java環境
1.安裝JAVA：
wget http://download.Oracle.com/otn-pub/java/jdk/8u60-b27/jdk-8u60-linux-x64.tar.gztar xf jdk-8u60-linux-x64.tar.gz -C /usr/local/cd /usr/local/ln -sv jdk1.8.0_60 jdk
2.配置環境變量：
vim /etc/PRofile.d/jdk.sh--------------------------------------------------->JAVA_HOME=/usr/local/jdkPATH=$JAVA_HOME/bin:$PATHexport JAVA_HOME PATH<---------------------------------------------------. /etc/profile.d/jdk.sh
二、兩臺機器安裝tomcat
1.安裝tomcat：
wget http://mirrors.cnnic.cn/apache/tomcat/tomcat-8/v8.0.24/bin/apache-tomcat-8.0.24.tar.gztar xf apache-tomcat-8.0.24.tar.gz -C /usr/local/cd /usr/local/ln -sv apache-tomcat-8.0.24 tomcat
2.配置環境變量：
vim /etc/profile.d/tomcat.sh--------------------------------------------------->CATALINA_BASE=/usr/local/tomcatPATH=$CATALINA_BASE/bin:$PATHexport PATH CATALINA_BASE<---------------------------------------------------. /etc/profile.d/tomcat.sh
3.查看tomcat及JAVA狀態：
catalina.sh version
4.提供啟動腳本：
vim /etc/init.d/tomcat-------------------------------------------------------->#!/bin/sh# Tomcat init script for Linux.## chkconfig: 2345 96 14# description: The Apache Tomcat servlet/jsp container.# JAVA_OPTS='-Xms64m -Xmx128m'JAVA_HOME=/usr/local/jdkCATALINA_HOME=/usr/local/tomcatexport JAVA_HOME CATALINA_HOMEcase $1 instart) exec $CATALINA_HOME/bin/catalina.sh start ;;stop) exec $CATALINA_HOME/bin/catalina.sh stop;;restart) $CATALINA_HOME/bin/catalina.sh stop sleep 2 exec $CATALINA_HOME/bin/catalina.sh start ;;*) echo "Usage: `basename $0` {start|stop|restart}" exit 1 ;;esac<--------------------------------------------------------chmod +x /etc/init.d/tomcatchkconfig --add tomcat5.編輯tomcat配置文件，只添加jvmRoute參數：
在19.66上：
vim /usr/local/tomcat/conf/server.xml-----------------------------------------------><Engine name="Catalina" defaultHost="localhost" jvmRoute="TomcatA"> //指明這是TomcatA主機
在19.74上：
vim /usr/local/tomcat/conf/server.xml-----------------------------------------------><Engine name="Catalina" defaultHost="localhost" jvmRoute="TomcatB">
6.提供測試頁面：
在19.66上：
mkdir -pv /usr/local/tomcat/webapps/test/WEB-INF/{classes,lib}vim /usr/local/tomcat/webapps/test/index.jsp------------------------------------------------------------------------><%@ page language="java" %><%@ page import="java.util.*" %><html> <head> <title>test</title> </head> <body> <% out.println("This is TomcatA"); %> </body></html>------------------------------------------------------------------------>service tomcat start在19.74上：
mkdir -pv /usr/local/tomcat/webapps/test/WEB-INF/{classes,lib}vim /usr/local/tomcat/webapps/test/index.jsp------------------------------------------------------------------------><%@ page language="java" %><%@ page import="java.util.*" %><html> <head> <title>test</title> </head> <body> <% out.println("This is TomcatB"); %> </body></html>------------------------------------------------------------------------>service tomcat start三、利用mod_jk模塊對tomcat進行負載均衡
利用httpd反向代理tomcat時有兩種方法，分別要用到mod_proxy和mod_jk這兩個模塊。mod_jk需要額外編譯安裝，而mod_proxy需要用到httpd的proxy_module、proxy_balancer_module、proxy_http_module、proxy_ajp_module模塊，確保安裝時這些模塊都被安裝了。從httpd2.2開始，這些模塊默認就是安裝的，所以這里我們直接用yum安裝即可。
下面先演示利用mod_jk模塊對tomcat進行負載均衡。此模塊只需要在一臺機器上安裝，我們這里在19.66上安裝。
1.安裝httpd：
yum -y install httpd httpd-devel //安裝httpd-devel為了提供apxs
2.安裝mod_jk.so模塊：
wget http://mirrors.cnnic.cn/apache/tomcat/tomcat-connectors/jk/tomcat-connectors-1.2.41-src.tar.gztar xf tomcat-connectors-1.2.41-src.tar.gzcd tomcat-connectors-1.2.41-src/native/./configure --with-apxs=/usr/sbin/apxsmake && make install
3.提供額外的httpd模塊配置文件：
vim /etc/httpd/conf.d/httpd-jk.conf------------------------------------------------------># Load the mod_jkLoadModule jk_module modules/mod_jk.so //加載mod_jk.so模塊JkWorkersFile /etc/httpd/conf.d/workers.properties //此模塊自己要用到的配置文件JkLogFile logs/mod_jk.logJkLogLevel debugJkMount /* lb1 //訪問根下的所有內容都發到集群lb1中來JkMount /status/ stat1
4.配置mod_jk模塊的配置文件workers.properties：
vim /etc/httpd/conf.d/workers.properties-------------------------------------------------------->worker.list = lb1,stat1worker.TomcatA.type = ajp13 //httpd連接tomcat所用的模式worker.TomcatA.host = 192.168.19.66worker.TomcatA.port = 8009worker.TomcatA.lbfactor = 1 //權重worker.TomcatB.type = ajp13worker.TomcatB.host = 192.168.19.74worker.TomcatB.port = 8009worker.TomcatB.lbfactor = 1worker.lb1.type = lb //調度方式worker.lb1.sticky_session = 0 //是否使用session綁定worker.lb1.balance_workers = TomcatA, TomcatBworker.stat1.type = status
5.啟動測試：
service httpd start
用瀏覽器打開http://192.168.19.66/test，我們不斷刷新，可以看到實驗效果。
四、利用mod_proxy模塊對tomcat進行負載均衡
1.仍然在19.66上編輯即可，使用http協議：
cd /etc/httpd/conf.d/mv httpd-jk.conf httpd-jk.conf.bakvim httpd-proxy.conf--------------------------------------------------------------><Proxy balancer://lb1> BalancerMember http://192.168.19.66:8080 loadfactor=1 route=TomcatA BalancerMember http://192.168.19.74:8080 loadfactor=1 route=TomcatB ProxySet lbmethod=byrequests //基于權重將統計請求個數進行調度</Proxy>ProxyPass / balancer://lb1/ProxyPassReverse / balancer://lb1/<--------------------------------------------------------------service httpd restart
2.使用ajp協議：
cd /etc/httpd/conf.d/mv httpd-jk.conf httpd-jk.conf.bakvim httpd-proxy.conf--------------------------------------------------------------><Proxy balancer://lb1> BalancerMember ajp://192.168.19.66:8009 loadfactor=1 route=TomcatA BalancerMember ajp://192.168.19.74:8009 loadfactor=1 route=TomcatB ProxySet lbmethod=byrequests</Proxy>ProxyPass / balancer://lb1/ProxyPassReverse / balancer://lb1/<--------------------------------------------------------------service httpd restart
以上兩種辦法都可以實現負載均衡，刷新頁面仍然可以看到效果，這里就不在給出圖片了。至此，實驗全部結束，謝謝！如有問題，請聯系我，QQ：82800452.
新聞熱點
疑難解答
