一、tomcat

        Tomcat是Java语言开发的，Tomcat服务器是一个免费的开放源代码的Web应用服务器，是Apache软件基金会的Jakarta项目中的一个核心项目,由Apache、Sun和其他一些公司及个人共同开发而成。Tomcat属于轻量级应用服务器，在中小型系统和并发访问用户不是很多的场合下被普遍使用，是开发和调试JSP程序的首选。一般来说，Tomcat虽然和Apache或者Nginx这些Web服务器一样，具有处理HTML页面的功能，然而由于其处理静态HTML的能力远不及Apache或者Nginx，所以Tomcat通常是作为一个Servlet和JSP容器，单独运行在后端。

1.安装jdk

[root@tomcat-node1 ~]# yum install -y java-1.8.0-openjdk.x86_64

2.解压tomcat

[root@tomcat-node1 ~]# tar -zxvf apache-tomcat-9.0.93.tar.gz -C /usr/local/

3.设置软连接

[root@tomcat-node1]# cd /usr/local
[root@tomcat-node1 local]# ln -s apache-tomcat-9.0.93 tomcat

4.开启tomcat

[root@tomcat-node1 ~]# /usr/local/tomcat/bin/startup.sh

5.生成tomcat主配置文件

[root@tomcat-node1 ~]# vim /usr/local/tomcat/conf/tomcat.conf
JAVA_HOME=/etc/alternatives/jre_openjdk

6.创建用户

[root@tomcat-node1 ~]# useradd -s /sbin/nologin -M tomcat

7.生成启动文件

# 修改权限
[root@tomcat-node1 ~]# chown -R tomcat.tomcat /usr/local/tomcat/
[root@tomcat-node1 ~]# vim /lib/systemd/system/tomcat.service 
[Unit]
Description=Tomcat
#After=syslog.target network.target remote-fs.target nss-lookup.target
After=syslog.target network.target
[Service]
Type=forking
EnvironmentFile=/usr/local/tomcat/conf/tomcat.conf
ExecStart=/usr/local/tomcat/bin/startup.sh
ExecStop=/usr/local/tomcat/bin/shutdown.sh
PrivateTmp=true
User=tomcat
Group=tomcat
[Install]
WantedBy=multi-user.target
[root@tomcat-node1 ~]# systemctl daemon-reload 

8.重启tomcat

[root@tomcat-node1 ~]# systemctl restart tomcat

 另一台主机同上

[root@tomcat-node2 ~]# yum install -y java-1.8.0-openjdk.x86_64
[root@tomcat-node2 ~]# tar -zxvf apache-tomcat-9.0.93.tar.gz -C /usr/local/
[root@tomcat-node2 ~]# vim /usr/local/tomcat/conf/tomcat.conf
JAVA_HOME=/etc/alternatives/jre_openjdk
[root@tomcat-node2 ~]# useradd -s /sbin/nologin -M tomcat
[root@tomcat-node2 ~]# vim /usr/local/tomcat/conf/tomcat.conf
JAVA_HOME=/etc/alternatives/jre_openjdk
# 修改权限
[root@tomcat-node2 ~]# chown -R tomcat.tomcat /usr/local/tomcat/
[root@tomcat-node2 ~]# vim /lib/systemd/system/tomcat.service 
[Unit]
Description=Tomcat
#After=syslog.target network.target remote-fs.target nss-lookup.target
After=syslog.target network.target
[Service]
Type=forking
EnvironmentFile=/usr/local/tomcat/conf/tomcat.conf
ExecStart=/usr/local/tomcat/bin/startup.sh
ExecStop=/usr/local/tomcat/bin/shutdown.sh
PrivateTmp=true
User=tomcat
Group=tomcat
[Install]
WantedBy=multi-user.target
[root@tomcat-node2 ~]# systemctl daemon-reload 
[root@tomcat-node2 ~]# systemctl restart tomcat

二、反向代理实现Tomcat

2.1 常见部署方式

准备一台安装好nignx的服务器

2.2 Nginx反向代理

反向代理单台web服务器

[root@nginx-node1 ~]# vim /usr/local/nginx/conf.d/vhost.conf 
server {
    listen *:80;
    server_name www.lm.org;
    root /data/wb/html;
    index index.html;
    location ~ \.jsp$ {
        proxy_pass http://172.25.254.10:8080;
    }
}
[root@nginx-node1 ~]# systemctl restart nginx

2.3 负载均衡

1.ip_hash

[root@nginx-node1 ~]# vim /usr/local/nginx/conf.d/vhost.conf 
upstream tomcat {
    ip_hash;
    #hash $cookie_JSESSIONID;
    server 172.25.254.10:8080;
    server 172.25.254.20:8080;
}
server {
    listen *:80;
    server_name www.lm.org;
    root /data/wb/html;
    index index.html;
    location ~ \.jsp$ {
        proxy_pass http://tomcat;
    }
}
[root@nginx-node1 ~]# systemctl restart nginx

源地址哈希，后端服务器不会改变 

2.cookie哈希

[root@nginx-node1 ~]# vim /usr/local/nginx/conf.d/vhost.conf 
upstream tomcat {
    #ip_hash;
    hash $cookie_JSESSIONID;
    server 172.25.254.10:8080;
    server 172.25.254.20:8080;
}
server {
    listen *:80;
    server_name www.lm.org;
    root /data/wb/html;
    index index.html;
    location ~ \.jsp$ {
        proxy_pass http://tomcat;
    }
}
[root@nginx-node1 ~]# systemctl restart nginx

三、session 共享服务器

msm

1.解压

[root@tomcat-node1 ~]# tar -zxvf apache-tomcat-9.0.93.tar.gz -C /usr/local/

2.复制

[root@tomcat-node1 ~]# cp test.jsp /usr/local/tomcat/webapps/
[root@tomcat-node1 ~]# scp test.jsp root@172.25.254.20:/usr/local/tomcat/webapps/
root@172.25.254.20's password: 
test.jsp                                                         100%  968   409.9KB/s   00:00  

3. 修改tomcat

172.25.254.10

[root@tomcat-node2 ~]# vim /usr/local/tomcat/conf/context.xml
    <Manager className="de.javakaffee.web.msm.MemcachedBackupSessionManager"
      memcachedNodes="m1:172.25.254.10:11211,m2:172.25.254.20:11211"
      failoverNodes="m1"
      requestUriIgnorePattern=".*\.(ico|png|gif|jpg|css|js)$"
      transcoderFactoryClass="de.javakaffee.web.msm.serializer.kryo.KryoTranscoderFactory"
    />
[root@tomcat-node1 ~]# systemctl restart tomcat.service

172.25.254.20

[root@tomcat-node2 ~]# vim /usr/local/tomcat/conf/context.xml
<Manager className="de.javakaffee.web.msm.MemcachedBackupSessionManager"
      memcachedNodes="m1:172.25.254.10:11211,m2:172.25.254.20:11211"
      failoverNodes="m2"
      requestUriIgnorePattern=".*\.(ico|png|gif|jpg|css|js)$"
      transcoderFactoryClass="de.javakaffee.web.msm.serializer.kryo.KryoTranscoderFactory"
    />
[root@tomcat-node2 ~]# systemctl restart tomcat.service

4.下载

[root@tomcat-node2 ~]# yum install -y memcached

 

[root@tomcat-node1 ~]# yum install -y memcached

测试