10.19. tomcat配合redis会话管理¶
这里使用192.168.46.151作为调度器，后端使用192.168.46.152，192.168.46.153作为tomcat服务器。
10.19.1. tomcat安装¶
[root@centos-152 ~]# yum search openjdk
[root@centos-152 ~]# yum install java-1.8.0-openjdk.x86_64
[root@centos-152 ~]# java -version
[root@centos-152 ~]# yum install tomcat tomcat-lib tomcat-admin-webapps tomcat-webapps tomcat-docs-webapp
[root@centos-152 ~]# systemctl restart tomcat
[root@centos-152 ~]# ss -tul
[root@centos-153 ~]# yum search openjdk
[root@centos-153 ~]# yum install java-1.8.0-openjdk.x86_64
[root@centos-153 ~]# java -version
[root@centos-153 ~]# yum install tomcat tomcat-lib tomcat-admin-webapps tomcat-webapps tomcat-docs-webapp
[root@centos-153 ~]# systemctl restart tomcat
[root@centos-153 ~]# ss -tul
10.19.2. 前端调度配置¶
[root@centos-151 ~]# yum install nginx
[root@centos-151 ~]# vim /etc/nginx/nginx.conf
# 添加和修改如下内容
upstream webend {
server 192.168.46.152;
server 192.168.46.153;
}
server {
listen 80 default_server;
listen [::]:80 default_server;
server_name _;
root /usr/share/nginx/html;
# Load configuration files for the default server block.
include /etc/nginx/default.d/*.conf;
location / {
proxy_pass http://webend ;
index index.jsp index.html;
}
[root@centos-151 ~]# systemctl restart nginx
[root@centos-151 ~]# ss -tunl
10.19.3. 后端tomcat样例页准备¶
[root@centos-152 ~]# mkdir -pv /usr/share/tomcat/webapps/test/{classes,lib,WEB-INF,META-INF}
[root@centos-152 ~]# vim /usr/share/tomcat/webapps/test/index.jsp
[root@centos-152 ~]# cat /usr/share/tomcat/webapps/test/index.jsp
<%@ page language="java" %>
<html>
<head><title>TomcatA</title></head>
<body>
<h1><font color="red">TomcatA.linuxpanda.tech</font></h1>
<table align="centre" border="1">
<tr>
<td>Session ID</td>
<% session.setAttribute("linuxpanda.tech","linuxpanda.tech"); %>
<td><%= session.getId() %></td>
</tr>
<tr>
<td>Created on</td>
<td><%= session.getCreationTime() %></td>
</tr>
</table>
</body>
</html>
[root@centos-152 ~]# scp -rp /usr/share/tomcat/webapps/test/ 192.168.46.153:/usr/share/tomcat/webapps/
[root@centos-153 ~]# vim /usr/share/tomcat/webapps/test/index.jsp
[root@centos-153 ~]# cat /usr/share/tomcat/webapps/test/index.jsp
<%@ page language="java" %>
<html>
<head><title>TomcatA</title></head>
<body>
<h1><font color="red">TomcatB.linuxpanda.tech</font></h1>
<table align="centre" border="1">
<tr>
<td>Session ID</td>
<% session.setAttribute("linuxpanda.tech","linuxpanda.tech"); %>
<td><%= session.getId() %></td>
</tr>
<tr>
<td>Created on</td>
<td><%= session.getCreationTime() %></td>
</tr>
</table>
</body>
</html>
# 启动tomcat
[root@centos-152 ~]# systemctl restart tomcat
[root@centos-153 ~]# systemctl restart tomcat
10.19.4. 测试调度情况¶
不断刷新，发现页面和sesssionId,都会不断变化的，chroom浏览器测试有点问题，建议firefox浏览器测试。
10.19.5. 配置tomcat支持memcached会话管理¶
# 查看tomcat版本
[root@centos-152 msm]# yum info tomcat |grep Version
Version : 7.0.76
# 先下载下会话管理对应的包
[root@centos-152 ~]# wget http://repo1.maven.org/maven2/de/javakaffee/msm/memcached-session-manager/2.3.0/memcached-session-manager-2.3.0.jar
[root@centos-152 ~]# wget http://repo1.maven.org/maven2/de/javakaffee/msm/memcached-session-manager-tc7/2.3.0/memcached-session-manager-tc7-2.3.0.jar
[root@centos-152 ~]# wget http://central.maven.org/maven2/redis/clients/jedis/2.9.0/jedis-2.9.0.jar
# 下载序列化需要的包
[root@centos-152 ~]# wget http://repo1.maven.org/maven2/org/objenesis/objenesis/2.6/objenesis-2.6.jar
[root@centos-152 ~]# wget http://repo1.maven.org/maven2/org/ow2/asm/asm/6.1.1/asm-6.1.1.jar
[root@centos-152 ~]# wget http://repo1.maven.org/maven2/com/esotericsoftware/reflectasm/1.11.3/reflectasm-1.11.3.jar
[root@centos-152 ~]# wget http://repo1.maven.org/maven2/com/esotericsoftware/minlog/1.3.0/minlog-1.3.0.jar
[root@centos-152 ~]# wget http://repo1.maven.org/maven2/com/esotericsoftware/kryo/4.0.2/kryo-4.0.2.jar
[root@centos-152 ~]# wget http://repo1.maven.org/maven2/de/javakaffee/kryo-serializers/0.42/kryo-serializers-0.42.jar
[root@centos-152 ~]# wget http://repo1.maven.org/maven2/de/javakaffee/msm/msm-kryo-serializer/2.3.0/msm-kryo-serializer-2.3.0.jar
# 查看下载的包
[root@centos-152 msm]# ll
total 1392
-rw-r--r-- 1 root root 108252 Mar 25 22:20 asm-6.1.1.jar
-rw-r--r-- 1 root root 553762 Jul 22 2016 jedis-2.9.0.jar
-rw-r--r-- 1 root root 337512 Mar 21 05:02 kryo-4.0.2.jar
-rw-r--r-- 1 root root 106032 Jul 17 2017 kryo-serializers-0.42.jar
-rw-r--r-- 1 root root 167266 Mar 19 06:29 memcached-session-manager-2.3.0.jar
-rw-r--r-- 1 root root 11704 Mar 19 06:33 memcached-session-manager-tc7-2.3.0.jar
-rw-r--r-- 1 root root 5711 Jul 21 2014 minlog-1.3.0.jar
-rw-r--r-- 1 root root 38268 Mar 19 06:37 msm-kryo-serializer-2.3.0.jar
-rw-r--r-- 1 root root 55684 Jun 20 2017 objenesis-2.6.jar
-rw-r--r-- 1 root root 20883 May 9 2016 reflectasm-1.11.3.jar
# 复制到tomcat的lib目录去
[root@centos-152 msm]# cp *.jar /usr/share/tomcat/lib/
[root@centos-152 msm]# scp *.jar 192.168.46.153:/usr/share/tomcat/lib/
[root@centos-152 msm]# vim /etc/tomcat/server.xml
# 在默认的Host片段添加如下内容
<Context path="/test" docBase="/usr/share/tomcat/webapps/test" reloadable="" >
<Manager className="de.javakaffee.web.msm.MemcachedBackupSessionManager"
memcachedNodes="redis://redis.linuxpanda.tech"
sticky="true"
sessionBackupAsync="false"
lockingMode="uriPattern:/path1|/path2"
requestUriIgnorePattern=".*\.(ico|png|gif|jpg|css|js)$"
transcoderFactoryClass="de.javakaffee.web.msm.serializer.kryo.KryoTranscoderFactory"
/>
</Context>
[root@centos-152 msm]# scp /etc/tomcat/server.xml 192.168.46.153:/etc/tomcat/
# 安装memcached
[root@centos-152 msm]# yum install redis
[root@centos-152 msm]# systemctl start redis
[root@centos-152 msm]# systemctl restart tomcat
[root@centos-153 msm]# yum install redis
[root@centos-153 msm]# systemctl start redis
[root@centos-153 msm]# systemctl restart tomcat
上面使用了”redis://redis.linuxpanda.tech”，不像memcached一样可以指定多个节点， 但是redis自身是支持集群的， 我们需要配置redis集群和Sentinel监控迁移即可， 但是这个配置文件写的是redis.linuxpanda.tech 所以就有问题了， 如果一个redis集群节点down掉，即使redis迁移到从节点上去， 我们的配置还是需要修改的，
这里给几种解决方案：
可以使用域名配合dns去做，
或者使用keepalived来做ip漂移。
上面2中配合zabbix监控可能更好些。