Nginx+Tomcat Load Balancing Cluster Setup

Keywords: Linux Nginx Tomcat vim JSP

Introduction to Tomcat

Tomcat was originally developed by Sun's software architect James Duncan Davidson
The directories and files below the installation path after Tomcat is installed are important files for using or configuring Tomcat

Tomcat Important Catalog

bin: Stores Tomcat scripts to start and close
conf: Store different Tomcat configuration files
doc: Store Tomcat documents
Lib/Japanese ser/common: Store library files needed for Tomcat to run
logs: Stores the LOG file for Tomcat execution
src: Stores Tomcat's source code
webapps:Tomcat's main Web publishing directory
work: Stores the class file generated by jsp compilation

Nginx Application

Nginx is a very good HTTP server software
- Support responses up to 50,000 concurrent connections
- Powerful static resource handling
- Stable operation
- Very low consumption of system resources such as memory, CPU, etc.
Currently, many large websites use Nginx servers as reverse proxies and load balancers for back-end Web site programs to improve the load concurrency of the entire site

Nginx Load Balancing Implementation Principle

Load balancing with Nginx is achieved through reverse proxy
Reverse Proxy Principle

Main parameters for Nginx configuration reverse proxy

upstream service pool name {}
- Configure the back-end server pool to provide response data
proxy_pass http://service pool name
- Configure server processing that forwards access requests to the back-end server pool

Nginx+Tomcat Load Balancing Cluster Experiment

Experimental environment

Nginx server IP address: 192.168.80.177
 Tomcat1 server IP address: 192.168.80.151
 Tomcat2 server IP address: 192.168.80.178
 client tester

Set up load balancing

Install and configure Tomcat services on Tomcat1, Tomcat2 servers (the Tomcat2 web page content is the same as other accp configurations)

[root@tomcat1 ~]# systemctl stop firewalld.service //close firewall
[root@tomcat1 ~]# mkdir /abc
[root@tomcat1 ~]# mount.cifs //192.168.100.8/LNMP-C7 /abc/
[root@tomcat1 ~]# cd /abc/tomcat/
[root@tomcat1 tomcat]# Tar zxvf jdk-8u91-linux-x64.tar.gz-C/usr/local/ //decompress JDK
[root@tomcat1 tomcat]# Vim/etc/profile//Configure environment variables
...
export JAVA_HOME=/usr/local/jdk1.8.0_91
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib
export PATH=${JAVA_HOME}/bin:$PATH
[root@tomcat1 tomcat]# Source/etc/profile//refresh profile
[root@tomcat1 tomcat]# Tar zxvf apache-tomcat-8.5.16.tar.gz-C/usr/local/ //decompression
[root@tomcat1 tomcat]# cd /usr/local/
[root@tomcat1 local]# mv apache-tomcat-8.5.16/ tomcat
[root@tomcat1 local]# Ln-s/usr/local/tomcat/bin/startup.sh/usr/local/bin//Start and close scripts for system identification
[root@tomcat1 local]# ln -s /usr/local/tomcat/bin/shutdown.sh /usr/local/bin/
[root@tomcat1 local]# Mkdir-p/web/webapp1 //create site
[root@tomcat1 local]# Vim/web/webapp1/index.jsp //Write JSP Web page content
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<html>
<head>
<title>JSP test1 page</title>
</head>
<body>
<% out.println("Welcome KGC Web");%>         //Output Information
</body>
</html>
[root@tomcat1 local]# Vim/usr/local/tomcat/conf/server.xml //Modify Tomcat configuration file
        <Host name="localhost"  appBase="webapps"
                    unpackWARs="true" autoDeploy="true">
            <Context docBase="/web/webapp1" path="" reloadable="false">  ##Add Site Information
            </Context>
[root@tomcat1 ~]# startup.sh //Start the service

Install and configure the Nginx service on the Nginx server

[root@nginx ~]# systemctl stop firewalld.service    ##Close Firewall
[root@nginx ~]# setenforce 0
[root@nginx ~]# yum install pcre-devel zlib-devel gcc gcc-c++ make -y  ##Install Environment Requirements
[root@nginx ~]# mkdir /abc
[root@nginx ~]# mount.cifs //192.168.100.3/LNMP-C7/abc/ ##Mount
Password for root@//192.168.100.3/LNMP-C7:  
[root@nginx ~]# cd /abc/
[root@nginx abc]# tar zxvf nginx-1.12.2.tar.gz -C /usr/local/  ##decompression
[root@nginx abc]# useradd -M -s /sbin/nologin nginx   ##Create System User
[root@nginx abc]# cd /usr/local/nginx-1.12.2/
[root@nginx nginx-1.12.2]# ./configure \   ##To configure
> --prefix=/usr/local/nginx \
> --user=nginx \
> --group=nginx \
> --with-http_stub_status_module \
> --with-http_gzip_static_module \
> --with-http_flv_module 
[root@nginx nginx-1.12.2]# make && make install   ##Compile Installation 
[root@nginx nginx-1.12.2]# vim /usr/local/nginx/conf/nginx.conf
#keepalive_timeout  0;
    keepalive_timeout  65;

    #gzip  on;

    upstream tomcat-server {                             #Add Address Pool
                        server 192.168.80.151:8080 weight=1;
                        server 192.168.80.178:8080 weight=1;    
                    }

    server {
            listen       80;
.....ellipsis
location / {
                    root   html;
                    index  index.html index.htm;
                    proxy_pass http://tomcat-server; #Add proxy, call server address pool
            }
[root@nginx nginx-1.12.2]# ln -s /usr/local/nginx/sbin/nginx /usr/local/sbin/  ##Easy system identification
[root@nginx nginx-1.12.2]# nginx   ##Open Service

Using client tester to access nginx proxy server

Dynamic and Static Separation

Modify the Nginx configuration file on the Nginx server

[root@nginx nginx-1.12.2]# Vim/etc/init.d/nginx //Write service startup script
#!/bin/bash
# chkconfig: - 99 20
# description: Nginx Service Control Script
PROG="/usr/local/nginx/sbin/nginx"
PIDF="/usr/local/nginx/logs/nginx.pid"
case "$1" in
start)
    $PROG
    ;;
stop)
    kill -s QUIT $(cat $PIDF)
    ;;
restart)
    $0 stop
    $0 start
    ;;
reload)
    kill -s HUP $(cat $PIDF)
    ;;
*)
            echo "Usage: $0 {start|stop|restart|reload}"
            exit 1
esac
exit 0
[root@nginx nginx-1.12.2]# chmod +x /etc/init.d/nginx 
[root@nginx nginx-1.12.2]# chkconfig --add nginx
[root@nginx nginx-1.12.2]# vim /usr/local/nginx/conf/nginx.conf
server {
...ellipsis...
 location ~.*.jsp$ {                  //Match jsp page Jump proxy pool
     proxy_pass http://tomcat-server;
     proxy_set_header Host $host;
 }
        location / {
    root   html/test;   ##Modify Site
    index  index.html index.htm;
    proxy_pass http://tomcat-server;
 }
[root@nginx nginx-1.12.2]# Vim/usr/local/nginx/html/index.html//Write static web pages
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
<title>Static Page</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Static Page</h1>
<p>This is a static page</p>
</body>
</html>
[root@nginx nginx-1.12.2]# service nginx stop    ##Turn Off Open Service
[root@nginx nginx-1.12.2]# service nginx start

Create jsp dynamic pages on Tomcat1, Tomcat2 servers

[root@tomcat1 ~]# mkdir /usr/local/tomcat/webapps/test
[root@tomcat1 ~]# vim /usr/local/tomcat/webapps/test/index.jsp
<!DOCTYPE html>
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ page import="java.util.Date" %>
<%@ page import="java.text.SimpleDateFormat" %> 
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/ html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Dynamic Page</title>
</head>
<body>
<div>Dynamic Page 1</div>
</body>
</html>
//Modify to Dynamic Page 2 on Tomcat2
//Access Static
http://192.168.13.177/  
//Access Dynamics  
http://192.168.13.177/test/index.jsp

Configure Nginx to process static pictures, Tomcat to process dynamic pages

Configure on two Tomcat servers

[root@tomcat1 ~]# vim /usr/local/tomcat/webapps/test/index.jsp
<body>
<div>Dynamic Page</div><br><img src="11.jpg"> //Add Page Picture 
</body>
[root@tomcat01 local]# vim /usr/local/tomcat/conf/server.xml 
//Append the following entry under line 149.
<Context docBase="/usr/local/tomcat/webapps/test" path="" reloadable="false">
</Context>
[root@tomcat1 test]# shutdown.sh //close restart
[root@tomcat1 test]# startup.sh