基于Apache和tomcat实现负载均衡

一、需要三台主机，一台安装apache，两台安装tomcat

二、tomcat1与tomcat2安装Tomcat tomcat-8.5.16（为了便于区分tomcat1使用默认页面，tomcat2使用测试页面）

安装tomcat之前需要安装java的jdk，版本为：jdk-8u191-linux-x64.tar.gz

1、第一台tomcat主机tomcat1（默认页面安装）

关闭防火墙

[root@localhost ~]# systemctl stop firewalld
[root@localhost ~]# iptables -F
[root@localhost ~]# setenforce 0

查看JDK是否安装

[root@localhost ~]# java -version
openjdk version "1.8.0_222"
OpenJDK Runtime Environment (build 1.8.0_222-b10)
OpenJDK 64-Bit Server VM (build 25.222-b10, mixed mode)

卸载用rpm方式安装的JDK

[root@localhost ~]# which java
/usr/bin/java

[root@localhost ~]# rm -rf /usr/bin/java

[root@localhost ~]# java -version
-bash: /usr/bin/java: 没有那个文件或目录

安装JDK

[root@localhost ~]# tar -xf jdk-8u191-linux-x64.tar.gz

[root@localhost ~]# mv jdk1.8.0_191/ /usr/local/java  //将解压后的包移动到指定目录下

[root@localhost ~]# /usr/local/java/bin/java -version  //此时只有通过绝对路径才可以查看java的版本号信息

[root@localhost ~]# vim /etc/profile  //修改

export JAVA_HOME=/usr/local/java  //设置java的根目录

export PATH=$PATH:$JAVA_HOME/bin  //在PATH环境变量中添加java根目录下的bin子目录

[root@localhost ~]# echo $PATH  //在未执行修改的脚本时查看PATH变量
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin  
[root@localhost ~]# source /etc/profile  //重置一下脚本
[root@localhost ~]# echo $PATH  //再查一遍
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin:/usr/local/java/bin

Tomcat安装

[root@localhost ~]# tar -xf apache-tomcat-8.5.16.tar.gz

[root@localhost ~]# mv apache-tomcat-8.5.16 /usr/local/tomcat8

[root@localhost ~]# ls /usr/local/tomcat8/bin
bootstrap.jar setclasspath.sh
catalina.bat shutdown.bat
catalina.sh shutdown.sh
catalina-tasks.xml startup.bat
commons-daemon.jar startup.sh （启动文件）
commons-daemon-native.tar.gz tomcat-juli.jar
configtest.bat tomcat-native.tar.gz
configtest.sh tool-wrapper.bat
daemon.sh tool-wrapper.sh
digest.bat version.bat
digest.sh version.sh
setclasspath.bat

//.bat  Windows版本

//.sh   Linus版本

启动

[root@localhost ~]# /usr/local/tomcat8/bin/startup.sh 
Using CATALINA_BASE: /usr/local/tomcat8
Using CATALINA_HOME: /usr/local/tomcat8
Using CATALINA_TMPDIR: /usr/local/tomcat8/temp
Using JRE_HOME: /usr/local/java
Using CLASSPATH: /usr/local/tomcat8/bin/bootstrap.jar:/usr/local/tomcat8/bin/tomcat-juli.jar
Tomcat started.

[root@localhost ~]# netstat -anpt | grep :8080
tcp6 0 0 :::8080 :::* LISTEN 3226/java

2、第二台tomcat主机tomcat2（测试页面安装）

安装tomcat的过程与安装第一台一样，过程省略

主要设置tomcat网页存放位置

[root@localhost ~]# mkdir -p /web/webapp/     //创建存放网页的目录
[root@localhost ~]# vim /web/webapp/index.jsp   //添加要存放的网页
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<html>
        <head>
                <title>JSP test1 page</title>
        </head>
        <body>
                <% out.println("Welcome to test site,http://www.test1.com");%>
        </body>
</html>

[root@localhost ~]# vim /usr/local/tomcat8/conf/server.xml
<Host name="localhost"  appBase="webapps"
            unpackWARs="true" autoDeploy="true">
        <Context docBase="/web/webapp" path="" reloadable="flash"></Context>

注释：docBase="/web/webapp"     //web应用的文档基准目录         
         path=" "                         //设置默认"类"
         reloadable="flase"       //设置监视"类"是否变化 

[root@localhost ~]# /usr/local/tomcat8/bin/shutdown.sh     //关一下机
Using CATALINA_BASE:   /usr/local/tomcat8
Using CATALINA_HOME:   /usr/local/tomcat8
Using CATALINA_TMPDIR: /usr/local/tomcat8/temp
Using JRE_HOME:        /usr/local/java
Using CLASSPATH:       /usr/local/tomcat8/bin/bootstrap.jar:/usr/local/tomcat8/bin/tomcat-juli.jar

[root@localhost ~]# /usr/local/tomcat8/bin/startup.sh   //重新开
Using CATALINA_BASE:   /usr/local/tomcat8
Using CATALINA_HOME:   /usr/local/tomcat8
Using CATALINA_TMPDIR: /usr/local/tomcat8/temp
Using JRE_HOME:        /usr/local/java
Using CLASSPATH:       /usr/local/tomcat8/bin/bootstrap.jar:/usr/local/tomcat8/bin/tomcat-juli.jar
Tomcat started.

网页测试

三、apache安装，Apache httpd-2.2.15，直接使用yum安装httpd

[root@localhost ~]# yum -y install httpd

修改配置文件

[root@localhost ~]# vim /etc/httpd/conf/httpd.conf
在文件里添加
<Proxy balancer://tomcat/>

BalancerMember ajp://192.168.200.111:8009/ loadfactor=1
BalancerMember ajp://192.168.200.112:8009/ loadfactor=1
proxyset lbmethod=byrequests
</Proxy>
proxyrequests off
ProxyPass / balancer://tomcat/
proxypassreverse / balancer://tomcats/
ProxyPass /server-status !
ProxyPass /balancer-manager !

[root@localhost ~]# systemctl restart httpd //重启服务

网页测试

原文地址：https://www.cnblogs.com/tanxiaojuncom/p/11552324.html