Implementation of Cluster with Tomcat8+Redis+Nginx
Realization of Cluster knowledge points by Tomcat8.5.14+Redis+Nginx
1) what is a cluster
A cluster is a group of independent computers interconnected through a high-speed network that form a group and are managed in a single system mode.
To put it bluntly, it is the same business, deployed on multiple servers.
2) problems encountered by the cluster
Session sharing
Session sharing based on NFS
Session sharing based on Database
Session sharing based on Cookie
Cache-based Session sharing (this is the option)
3) advantages of cluster
Improve performanc
Reduce the cost
Improve scalability
Enhance reliability
Test environment
JDK version: JDK8
Tomcat version: apache-tomcat-8.5.14
Redis version: redis-2.4.5
Nginx version: nginx-1.11.6
Required jar package
Put it under the lib folder under Tomcat:
Commons-pool2-2.4.2.jar
Jedis-2.9.0.jar
Javazhan-tomcat-redis-session.jar
Download address: Tomcat8+Redis to implement the Jar rack package http://down.51cto.com/data/2449143 required by the cluster
Modify the configuration file
1) Tomcat
Make two copies of apache-tomcat-8.5.14 and name them apache-tomcat-81 and apache-tomcat-82 respectively. The port of the server.xml needs to be modified in order to start both tomcat.
Service port
two。 Access connection port
The first connector listens on port 8080 and is responsible for establishing a HTTP connection. This connector is used when accessing the Web application of the Tomcat server through a browser.
3. Connect the port to the HTTP server
The second connector listens on port 8009 and is responsible for establishing connections with other HTTP servers. This connector is needed when integrating Tomcat with other HTTP servers.
Configure context.xml files: session shar
WEB-INF/web.xml
${catalina.base} / conf/web.xml
Description:
If you put manager in server.xml in your tomcat configuration, you will fail when you use maven for hot deployment. Therefore, it is recommended to put it in context.xml.
2) Nginx
Modify the nginx.conf file in the conf directory
Upstream javazhan.com {
Server yan.10010.com:8881 weight=5
Server yan.10010.com:8882 weight=5
}
Server {
Listen 80
Server_name api.xxx.com
Location /
{
Proxy_set_header Host $host
Proxy_set_header X-Real-Ip $remote_addr
Proxy_set_header X-Forwarded-For $remote_addr
Proxy_pass http://javazhan.com;
}
}
Create a new web project
Create a new folder ClusterTest, create a new sessiontest.jsp, and put it under webapps under the tomcat folder.
ClusterApp Test
Nginx IP visited:
Tomcat SessionPort:
0) {
String dataValue = request.getParameter ("dataValue")
Session.setAttribute (dataName, dataValue)
}
Out.println ("Session list"
")
System.out.println ("Session list")
Enumeration e = session.getAttributeNames ()
While (e.hasMoreElements ()) {
String name = (String) e.nextElement ()
String value = session.getAttribute (name). ToString ()
Out.println (name + "=" + value + ")
")
System.out.println (name + "=" + value)
}
% >
Name:
Value:
test
1) start nginx
2) start redis
3) start tomcat (two)
4) start the browser
5) enter the address http://yan.10010.com/ClusterTest/sessiontest.jsp
You can see that the same address accesses two tomcat servers respectively, and the session value remains the same, so session sharing is realized.
