常见的web集群调度器分为软件和硬件
软件：LVS Haproxy nginx
硬件： F5 Array 梭子鱼 绿盟
HAProxy和Nginx是基于第三方应用实现的软负载均衡；
HAProxy和Nginx都可以实现4层和7层技术，HAProxy可提供TCP和HTTP应用的负载均衡综合解决方案；
而HAProxy在状态监测方面功能更丰富、强大，可支持端口、URL、脚本等多种状态检测方式；
HAProxy功能强大，单纯从效率上来讲HAProxy会比Nginx有更出色的负载均衡速度，在并发处理上也是优于Nginx的。但整体性能低于4层模式的LVS负载均衡；
基于第三方应用实现软负载均衡，可以实现4层和7层技术；
Nginx主要用于Web服务器或缓存服务器。Nginx的upstream模块虽然也支持群集功能，但是性能没有LVS和Haproxy好，对群集节点健康检查功能不强，只支持通过端口来检测，不支持通过URL来
LVS基于Linux操作系统内核实现软负载均衡
LVS是可实现4层的IP负载均衡技术，无法实现基于目录、URL的转发
LVS因为工作在ISO模型的第四层，其状态监测功能单一
Haproxy是一款课提供高可用、负载均衡、及基于TCP和http应用的代理软件，通常用于并发大1万以上的web站点。通常这些站点又需要会话保持或七层处理，HAProxy的运行模式使得它可以很简单安全的整合至当前的架构中，同时可以保护web服务器不被暴露到网络上
●可靠性和稳定性非常好，可以与硬件级的F5负载均衡设备相媲美；
●最高可以同时维护40000-50000个并发连接，单位时间内处理的最大请求数为20000个，最大处理能力可达10Git/s；
●支持多达8种负载均衡算法
●支持Session会话保持，Cookie的引导；
●支持通过获取指定的url来检测后端服务器的状态；
●支持虚机主机功能，从而实现web负载均衡更加灵活；
●支持连接拒绝、全透明代理等独特的功能；
●拥有强大的ACL支持，用于访问控制；
●支持TCP和HTTP协议的负载均衡转发；
●支持客户端的keepalive功能，减少客户端与haproxy的多次三次握手导致资源浪费，让多个请求在一个tcp连接中完成
（1）roundrobin----------表示简单的轮询
（2）static-rr----------------表示根据权重
（3）leastconn-------------表示最少连接者先处理
（4）source-----------------表示根据请求源IP
（5）uri——————----表示根据请求的URI,做cdn需使用;
（6）url_param————表示根据请求的URl参数’balance url_param’ requires an URL parameter name
（7）hdr(name)——------表示根据HTTP请求头来锁定每一次HTTP请求;
（8）rdp-cookie(name)–表示根据cookie(name)来锁定并哈希每一次TCP请求。
HAProxy 提供了3种实现会话保持的方式
1）source（源地址hash）
2）设置cookie
3）会话粘性表stick-table
web1 192.168.65.104
web2 192.168.65.105
tomcat1 192.168.65.102:8080
tomcat2 192.168.65.102:8081
Haproxy 192.168.65.106
104
[root@localhost ~]# yum -y install nginx (用 nginx.repo安装的)
[root@localhost ~]# cd /usr/share/nginx.html
[root@localhost html]# mkdir static
[root@localhost html]#echo 'this is web1 page!' >static/test.html
[root@localhost ~]#systemctl start nginx
105
[root@localhost ~]# yum -y install nginx (用 nginx.repo安装的)
[root@localhost ~]# cd /usr/share/nginx.html
[root@localhost html]# mkdir static
[root@localhost html]#echo 'this is web2 page!' >static/test.html
[root@localhost ~]#systemctl start nginx
102
安装jdk
[root@localhost ~]#systemctl stop firewalld.service
[root@localhost ~]#setenforce 0
[root@localhost ~]#cd /opt
[root@localhost opt]#ls
apache-tomcat-8.5.16.tar.gz jdk-8u91-linux-x64.tar.gz rh
[root@localhost opt]#tar xf jdk-8u91-linux-x64.tar.gz
[root@localhost opt]#ls
apache-tomcat-8.5.16.tar.gz jdk1.8.0_91 jdk-8u91-linux-x64.tar.gz rh
[root@localhost opt]#mv jdk1.8.0_91/ /usr/local/
[root@localhost opt]#ls /usr/local/
bin etc games include jdk1.8.0_91 lib lib64 libexec sbin share src
[root@localhost opt]#cd /etc/profile.d/ #环境变量子配置文件
[root@localhost profile.d]#ls
256term.csh colorgrep.csh flatpak.sh less.sh vte.sh
256term.sh colorgrep.sh lang.csh PackageKit.sh which2.csh
abrt-console-notification.sh colorls.csh lang.sh vim.csh which2.sh
bash_completion.sh colorls.sh less.csh vim.sh
[root@localhost profile.d]#vim java.sh
export JAVA_HOME=/usr/local/jdk1.8.0_91
export JRE_HOME=$JAVA_HOME/jre
export CLASSPATH=.:$JAVA_HOME/lib:$JRE_HOME
export PATH=$JAVA_HOME/bin:$JRE_HOME/bin:$PATH
[root@localhost profile.d]#source java.sh
部署Tomcat
[root@localhost profile.d]#cd /opt
[root@localhost opt]#ls
apache-tomcat-8.5.16.tar.gz jdk-8u91-linux-x64.tar.gz rh
[root@localhost opt]#tar xf apache-tomcat-8.5.16.tar.gz
[root@localhost opt]#ls
apache-tomcat-8.5.16 apache-tomcat-8.5.16.tar.gz jdk-8u91-linux-x64.tar.gz rh
[root@localhost opt]#cp -a apache-tomcat-8.5.16 /usr/local/tomcat1
[root@localhost opt]#cp -a apache-tomcat-8.5.16 /usr/local/tomcat2
[root@localhost opt]#ls /usr/local/
bin games jdk1.8.0_91 lib64 sbin src tomcat2
etc include lib libexec share tomcat1
[root@localhost opt]#vim /usr/local/tomcat2/conf/server.xml
//修改tomcat2的配置文件
<Server port="8006" shutdown="SHUTDOWN">
#22行，修改Server prot，默认为8005 -> 修改为8006
<Connector port="8081" protocol="HTTP/1.1"
#69行，修改Connector port，HTTP/1.1 默认为8080 -> 修改为8081
[root@localhost opt]#cd /usr/local/tomcat2
[root@localhost tomcat2]#ls
bin conf lib LICENSE logs NOTICE RELEASE-NOTES RUNNING.txt temp webapps work
[root@localhost tomcat2]#cd bin
[root@localhost bin]#ls
bootstrap.jar configtest.bat setclasspath.sh tomcat-native.tar.gz
catalina.bat configtest.sh shutdown.bat tool-wrapper.bat
catalina.sh daemon.sh shutdown.sh tool-wrapper.sh
catalina-tasks.xml digest.bat startup.bat version.bat
commons-daemon.jar digest.sh startup.sh version.sh
commons-daemon-native.tar.gz setclasspath.bat tomcat-juli.jar
[root@localhost bin]#vim startup.sh
export CATALINA_BASE=/usr/local/tomcat2 #Tomcat存放的目录位置
export CATALINA_HOME=/usr/local/tomcat2
export TOMCAT_HOME=/usr/local/tomcat2
[root@localhost bin]#vim shutdown.sh
export CATALINA_BASE=/usr/local/tomcat2
export CATALINA_HOME=/usr/local/tomcat2
export TOMCAT_HOME=/usr/local/tomcat2
[root@localhost bin]#cd /usr/local/tomcat1
[root@localhost tomcat1]#ls
bin conf lib LICENSE logs NOTICE RELEASE-NOTES RUNNING.txt temp webapps work
[root@localhost tomcat1]#cd bin
[root@localhost bin]#ls
bootstrap.jar configtest.bat setclasspath.sh tomcat-native.tar.gz
catalina.bat configtest.sh shutdown.bat tool-wrapper.bat
catalina.sh daemon.sh shutdown.sh tool-wrapper.sh
catalina-tasks.xml digest.bat startup.bat version.bat
commons-daemon.jar digest.sh startup.sh version.sh
commons-daemon-native.tar.gz setclasspath.bat tomcat-juli.jar
[root@localhost bin]#vim startup.sh
export CATALINA_BASE=/usr/local/tomcat1
export CATALINA_HOME=/usr/local/tomcat1
export TOMCAT_HOME=/usr/local/tomcat1
[root@localhost bin]#vim shutdown.sh
export CATALINA_BASE=/usr/local/tomcat1
export CATALINA_HOME=/usr/local/tomcat1
export TOMCAT_HOME=/usr/local/tomcat1
[root@localhost bin]#/usr/local/tomcat1/bin/startup.sh
Using CATALINA_BASE: /usr/local/tomcat1
Using CATALINA_HOME: /usr/local/tomcat1
Using CATALINA_TMPDIR: /usr/local/tomcat1/temp
Using JRE_HOME: /usr/local/jdk1.8.0_91/jre
Using CLASSPATH: /usr/local/tomcat1/bin/bootstrap.jar:/usr/local/tomcat1/bin/tomcat-juli.jar
Tomcat started.
[root@localhost bin]#/usr/local/tomcat2/bin/startup.sh
Using CATALINA_BASE: /usr/local/tomcat2
Using CATALINA_HOME: /usr/local/tomcat2
Using CATALINA_TMPDIR: /usr/local/tomcat2/temp
Using JRE_HOME: /usr/local/jdk1.8.0_91/jre
Using CLASSPATH: /usr/local/tomcat2/bin/bootstrap.jar:/usr/local/tomcat2/bin/tomcat-juli.jar
Tomcat started.
[root@localhost bin]#netstat -ltnp |grep java
tcp6 0 0 :::8080 :::* LISTEN 40828/java
tcp6 0 0 :::8081 :::* LISTEN 40885/java
tcp6 0 0 127.0.0.1:8005 :::* LISTEN 40828/java
tcp6 0 0 127.0.0.1:8006 :::* LISTEN 40885/java
tcp6 0 0 :::8009 :::* LISTEN 40828/java
tcp6 0 0 :::8010 :::* LISTEN 40885/java
#编译安装Haproxy
yum install -y zlib-devel openssl-devel pcre-devel systemd-devel
[root@localhost opt]# useradd -M -s /sbin/nologin haproxy
[root@localhost opt]# tar xf haproxy-2.8.3.tar.gz
[root@localhost opt]# ls
haproxy-2.8.3 haproxy-2.8.3.tar.gz rh
[root@localhost opt]# cd haproxy-2.8.3/
[root@localhost haproxy-2.8.3]# make ARCH=x86_64 TARGET=linux-glibc USE_PCRE=1 USE_OPENSSL=1 USE_ZLIB=1 USE_SYSTEMD=1
[root@localhost haproxy-2.8.3]# make install PREFIX=/usr/local/haproxy
[root@localhost haproxy-2.8.3]# ls
addons CHANGELOG examples LICENSE reg-tests tests
admin CONTRIBUTING haproxy MAINTAINERS scripts VERDATE
BRANCHES dev include Makefile src VERSION
BSDmakefile doc INSTALL README SUBVERS
[root@localhost haproxy-2.8.3]# cd examples/
[root@localhost examples]# ls
basic-config-edge.cfg lua transparent_proxy.cfg
content-sw-sample.cfg option-http_proxy.cfg wurfl-example.cfg
errorfiles quick-test.cfg
haproxy.init socks4.cfg
[root@localhost examples]# mkdir /etc/haproxy
[root@localhost examples]# cp quick-test.cfg /etc/haproxy/haproxy.cfg
[root@localhost examples]# cp haproxy.init /etc/init.d/haproxy
[root@localhost examples]# cd /etc/haproxy/
[root@localhost haproxy]# ls
haproxy.cfg
[root@localhost haproxy]# cd /etc/init.d/
[root@localhost init.d]# ls
functions haproxy netconsole network README
[root@localhost init.d]# vim haproxy
[root@localhost init.d]# cd /usr/local/haproxy/
[root@localhost haproxy]# ls
doc sbin share
[root@localhost haproxy]# ln -s /usr/local/haproxy/sbin/haproxy /usr/sbin
[root@localhost haproxy]# haproxy -v
HAProxy version 2.8.3-86e043a 2023/09/07 - https://haproxy.org/
Status: long-term supported branch - will stop receiving fixes around Q2 2028.
Known bugs: http://www.haproxy.org/bugs/bugs-2.8.3.html
Running on: Linux 3.10.0-693.el7.x86_64 #1 SMP Tue Aug 22 21:09:27 UTC 2017 x86_64
[root@localhost haproxy]# chmod +x /etc/init.d/haproxy
[root@localhost haproxy]# chkconfig --add haproxy
[root@localhost haproxy]# chkconfig --list haproxy
注：该输出结果只显示 SysV 服务，并不包含
原生 systemd 服务。SysV 配置数据
可能被原生 systemd 配置覆盖。
要列出 systemd 服务，请执行 'systemctl list-unit-files'。
查看在具体 target 启用的服务请执行
'systemctl list-dependencies [target]'。
haproxy 0:关 1:关 2:关 3:关 4:关 5:关 6:关
[root@localhost haproxy]# chkconfig --level 35 haproxy on
[root@localhost haproxy]# chkconfig --list haproxy
注：该输出结果只显示 SysV 服务，并不包含
原生 systemd 服务。SysV 配置数据
可能被原生 systemd 配置覆盖。
要列出 systemd 服务，请执行 'systemctl list-unit-files'。
查看在具体 target 启用的服务请执行
'systemctl list-dependencies [target]'。
haproxy 0:关 1:关 2:关 3:开 4:关 5:开 6:关
[root@localhost haproxy]# service haproxy start
Starting haproxy (via systemctl): [ 确定 ]
[root@localhost haproxy]# netstat -lntp |grep haproxy
tcp 0 0 0.0.0.0:8000 0.0.0.0:* LISTEN 3110/haproxy
[root@localhost haproxy]# vim haproxy.cfg
global
log 127.0.0.1 local0 info
log 127.0.0.1 local1 warning
maxconn 30000
#chroot /var/lib/haproxy
pidfile /var/run/haproxy.pid
user haproxy
group haproxy
daemon
#nbproc 1
spread-checks 2
defaults
log global
mode http
option http-keep-alive
option forwardfor
option httplog
option dontlognull
option redispatch
option abortonclose
maxconn 20000
retries 3
#contimeout 5000
#clitimeout 50000
#srvtimeout 50000
timeout http-request 2s
timeout queue 3s
timeout connect 1s
timeout client 10s
timeout server 2s
timeout http-keep-alive 10s
timeout check 2s
frontend mm-http
bind 0.0.0.0:80
acl url_static path_beg -i /static
acl url_dynamic path_end -i .jsp
use_backend static_backend if url_static
use_backend dynamic_backend if url_dynamic
default_backend static_backend
backend static_backend
balance roundrobin
option httpchk GET /index.html
server static_inst01 192.168.65.104:80 check inter 2000 rise 2 fall 3
server static_inst02 192.168.65.105:80 check inter 2000 rise 2 fall 3
backend dynamic_backend
balance roundrobin
option http-server-close
server dynamic_inst01 192.168.65.102:8080 check
server dynamic_inst02 192.168.65.102:8081 check
listen stats
bind *:1080
stats enable
stats refresh 30s
stats uri /stats
stats realm HAProxy\ Stats
stats auth admin:admin
service haproxy restart
Restarting haproxy (via systemctl): [ 确定 ]
[root@localhost haproxy]# netstat -lntp |grep haproxy
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 17869/haproxy
tcp 0 0 0.0.0.0:1080 0.0.0.0:* LISTEN 17869/haproxy
在网页输入以下网址
http://192.168.65.106/static/test.html
http://192.168.65.106/mm/test.jsp
[root@localhost haproxy]# vim haproxy.cfg
backend dynamic_backend
balance roundrobin
option http-server-close
cookie HA_STICKY_dy insert indirect nocache#实现会话保持，不能刷新了
server dynamic_inst01 192.168.65.102:8080 cookie appserver1 check
server dynamic_inst02 192.168.65.102:8081 cookie appserver1 check
在网页输入以下网址
http://192.168.65.106/static/test.html
http://192.168.65.106/mm/test.jsp