Tomcat 集群配置 Session共享

在实际web应用中，会有多台服务器来部署同一套web应用，通过负载均衡来减轻用户对同一台服务器的访问压力，该部署为集群部署，在集群部署中有一个问题，为在不同的服务器上如何共享Session，此时我们通过tomcat系统内的session共享技术来实现。

tomcat 1的配置文件如下，端口号8686：

<?xml version="1.0" encoding="UTF-8"?>
<!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor
license agreements. See the NOTICE file distributed with this work for additional
information regarding copyright ownership. The ASF licenses this file to
You under the Apache License, Version 2.0 (the "License"); you may not use
this file except in compliance with the License. You may obtain a copy of
the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required
by applicable law or agreed to in writing, software distributed under the
License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
OF ANY KIND, either express or implied. See the License for the specific
language governing permissions and limitations under the License. --><!-- Note: A "Server" is not itself a "Container", so you may not define
subcomponents such as "Valves" at this level. Documentation at /docs/config/server.html -->
<Server port="8605" shutdown="SHUTDOWN">
<!-- Security listener. Documentation at /docs/config/listeners.html <Listener
className="org.apache.catalina.security.SecurityListener" /> -->
<!--APR library loader. Documentation at /docs/apr.html -->
<Listener SSLEngine="on"
className="org.apache.catalina.core.AprLifecycleListener" />
<!--Initialize Jasper prior to webapps are loaded. Documentation at /docs/jasper-howto.html -->
<Listener className="org.apache.catalina.core.JasperListener" />
<!-- Prevent memory leaks due to use of particular java/javax APIs -->
<Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" />
<Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" />
<Listener className="org.apache.catalina.core.ThreadLocalLeakPreventionListener" />

<!-- Global JNDI resources Documentation at /docs/jndi-resources-howto.html -->
<GlobalNamingResources>
<!-- Editable user database that can also be used by UserDatabaseRealm
to authenticate users -->
<Resource auth="Container" description="User database that can be updated and saved"
factory="org.apache.catalina.users.MemoryUserDatabaseFactory" name="UserDatabase"
pathname="conf/tomcat-users.xml" type="org.apache.catalina.UserDatabase" />
</GlobalNamingResources>

<!-- A "Service" is a collection of one or more "Connectors" that share
a single "Container" Note: A "Service" is not itself a "Container", so you
may not define subcomponents such as "Valves" at this level. Documentation
at /docs/config/service.html -->
<Service name="Catalina">

<!--The connectors can use a shared executor, you can define one or more
named thread pools -->
<!-- <Executor name="tomcatThreadPool" namePrefix="catalina-exec-" maxThreads="150"
minSpareThreads="4"/> -->

<!-- A "Connector" represents an endpoint by which requests are received
and responses are returned. Documentation at : Java HTTP Connector: /docs/config/http.html
(blocking & non-blocking) Java AJP Connector: /docs/config/ajp.html APR (HTTP/AJP)
Connector: /docs/apr.html Define a non-SSL HTTP/1.1 Connector on port 8686 -->
<Connector connectionTimeout="20000" port="8686" protocol="HTTP/1.1"
redirectPort="8443" />
<!-- A "Connector" using the shared thread pool -->
<!-- <Connector executor="tomcatThreadPool" port="8686" protocol="HTTP/1.1"
connectionTimeout="20000" redirectPort="8443" /> -->
<!-- Define a SSL HTTP/1.1 Connector on port 8443 This connector uses the
JSSE configuration, when using APR, the connector should be using the OpenSSL
style configuration described in the APR documentation -->
<!-- <Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true" maxThreads="150"
scheme="https" secure="true" clientAuth="false" sslProtocol="TLS" /> -->

<!-- <Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true" maxThreads="150"
scheme="https" secure="true" keystoreFile="D:\hsinghsu.keystore" keystorePass="hsinghsu"
clientAuth="false" sslProtocol="TLS" /> -->

<!-- Define an AJP 1.3 Connector on port 8609 -->
<Connector port="8609" protocol="AJP/1.3" redirectPort="8443" />

<!-- An Engine represents the entry point (within Catalina) that processes
every request. The Engine implementation for Tomcat stand alone analyzes
the HTTP headers included with the request, and passes them on to the appropriate
Host (virtual host). Documentation at /docs/config/engine.html -->

<!-- You should set jvmRoute to support load-balancing via AJP ie : <Engine
name="Catalina" defaultHost="localhost" jvmRoute="jvm1"> -->
<Engine defaultHost="localhost" name="Catalina">

<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"
channelSendOptions="6">

<Manager className="org.apache.catalina.ha.session.BackupManager"
expireSessionsOnShutdown="false" notifyListenersOnReplication="true"
mapSendOptions="6" />

<Channel className="org.apache.catalina.tribes.group.GroupChannel">

<Membership className="org.apache.catalina.tribes.membership.McastService"
address="228.0.0.4" port="45564" frequency="500" dropTime="3000" />

<Receiver className="org.apache.catalina.tribes.transport.nio.NioReceiver"
address="auto" port="4001" selectorTimeout="100" maxThreads="6" />

<Sender className="org.apache.catalina.tribes.transport.ReplicationTransmitter">
<Transport className="org.apache.catalina.tribes.transport.nio.PooledParallelSender" />
</Sender>

<Interceptor className="org.apache.catalina.tribes.group.interceptors.TcpFailureDetector" />
<Interceptor className="org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor" />
<Interceptor className="org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor" />

</Channel>

<Valve className="org.apache.catalina.ha.tcp.ReplicationValve"
filter=".*\.gif;.*\.js;.*\.jpg;.*\.png;.*\.htm;.*\.html;.*\.css;.*\.txt;" />

<ClusterListener className="org.apache.catalina.ha.session.ClusterSessionListener" />

</Cluster>

<!--For clustering, please take a look at documentation at: /docs/cluster-howto.html
(simple how to) /docs/config/cluster.html (reference documentation) -->
<!-- <Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"/> -->

<!-- Use the LockOutRealm to prevent attempts to guess user passwords
via a brute-force attack -->
<Realm className="org.apache.catalina.realm.LockOutRealm">
<!-- This Realm uses the UserDatabase configured in the global JNDI resources
under the key "UserDatabase". Any edits that are performed against this UserDatabase
are immediately available for use by the Realm. -->
<Realm className="org.apache.catalina.realm.UserDatabaseRealm"
resourceName="UserDatabase" />
</Realm>

<Host appBase="webapps" autoDeploy="true" name="localhost"
unpackWARs="true">

<Context path="/testSession" docBase="D:\EclipseWorkspace\testSession\WebContent"
reloadable="true" />

<!-- SingleSignOn valve, share authentication between web applications
Documentation at: /docs/config/valve.html -->
<!-- <Valve className="org.apache.catalina.authenticator.SingleSignOn"
/> -->

<!-- Access log processes all example. Documentation at: /docs/config/valve.html
Note: The pattern used is equivalent to using pattern="common" -->
<!-- <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
pattern="%h %l %u %t "%r" %s %b" prefix="localhost_access_log."
suffix=".txt"/> -->
</Host>
</Engine>
</Service>
</Server>

tomcat 2的配置文件如下，端口号8080：

<?xml version="1.0" encoding="UTF-8"?>
<!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor
license agreements. See the NOTICE file distributed with this work for additional
information regarding copyright ownership. The ASF licenses this file to
You under the Apache License, Version 2.0 (the "License"); you may not use
this file except in compliance with the License. You may obtain a copy of
the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required
by applicable law or agreed to in writing, software distributed under the
License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
OF ANY KIND, either express or implied. See the License for the specific
language governing permissions and limitations under the License. --><!-- Note: A "Server" is not itself a "Container", so you may not define
subcomponents such as "Valves" at this level. Documentation at /docs/config/server.html -->
<Server port="8005" shutdown="SHUTDOWN">
<!-- Security listener. Documentation at /docs/config/listeners.html <Listener
className="org.apache.catalina.security.SecurityListener" /> -->
<!--APR library loader. Documentation at /docs/apr.html -->
<Listener SSLEngine="on"
className="org.apache.catalina.core.AprLifecycleListener" />
<!--Initialize Jasper prior to webapps are loaded. Documentation at /docs/jasper-howto.html -->
<Listener className="org.apache.catalina.core.JasperListener" />
<!-- Prevent memory leaks due to use of particular java/javax APIs -->
<Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" />
<Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" />
<Listener className="org.apache.catalina.core.ThreadLocalLeakPreventionListener" />

<!-- Global JNDI resources Documentation at /docs/jndi-resources-howto.html -->
<GlobalNamingResources>
<!-- Editable user database that can also be used by UserDatabaseRealm
to authenticate users -->
<Resource auth="Container" description="User database that can be updated and saved"
factory="org.apache.catalina.users.MemoryUserDatabaseFactory" name="UserDatabase"
pathname="conf/tomcat-users.xml" type="org.apache.catalina.UserDatabase" />
</GlobalNamingResources>

<!-- A "Service" is a collection of one or more "Connectors" that share
a single "Container" Note: A "Service" is not itself a "Container", so you
may not define subcomponents such as "Valves" at this level. Documentation
at /docs/config/service.html -->
<Service name="Catalina">

<!--The connectors can use a shared executor, you can define one or more
named thread pools -->
<!-- <Executor name="tomcatThreadPool" namePrefix="catalina-exec-" maxThreads="150"
minSpareThreads="4"/> -->

<!-- A "Connector" represents an endpoint by which requests are received
and responses are returned. Documentation at : Java HTTP Connector: /docs/config/http.html
(blocking & non-blocking) Java AJP Connector: /docs/config/ajp.html APR (HTTP/AJP)
Connector: /docs/apr.html Define a non-SSL HTTP/1.1 Connector on port 8686 -->
<Connector connectionTimeout="20000" port="8080" protocol="HTTP/1.1"
redirectPort="8443" />
<!-- A "Connector" using the shared thread pool -->
<!-- <Connector executor="tomcatThreadPool" port="8686" protocol="HTTP/1.1"
connectionTimeout="20000" redirectPort="8443" /> -->
<!-- Define a SSL HTTP/1.1 Connector on port 8443 This connector uses the
JSSE configuration, when using APR, the connector should be using the OpenSSL
style configuration described in the APR documentation -->
<!-- <Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true" maxThreads="150"
scheme="https" secure="true" clientAuth="false" sslProtocol="TLS" /> -->

<!-- <Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true" maxThreads="150"
scheme="https" secure="true" keystoreFile="D:\hsinghsu.keystore" keystorePass="hsinghsu"
clientAuth="false" sslProtocol="TLS" /> -->

<!-- Define an AJP 1.3 Connector on port 8609 -->
<Connector port="8009" protocol="AJP/1.3" redirectPort="8443" />

<!-- An Engine represents the entry point (within Catalina) that processes
every request. The Engine implementation for Tomcat stand alone analyzes
the HTTP headers included with the request, and passes them on to the appropriate
Host (virtual host). Documentation at /docs/config/engine.html -->

<!-- You should set jvmRoute to support load-balancing via AJP ie : <Engine
name="Catalina" defaultHost="localhost" jvmRoute="jvm1"> -->
<Engine defaultHost="localhost" name="Catalina">

<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"
channelSendOptions="6">

<Manager className="org.apache.catalina.ha.session.BackupManager"
expireSessionsOnShutdown="false" notifyListenersOnReplication="true"
mapSendOptions="6" />

<Channel className="org.apache.catalina.tribes.group.GroupChannel">

<Membership className="org.apache.catalina.tribes.membership.McastService"
address="228.0.0.4" port="45564" frequency="500" dropTime="3000" />

<Receiver className="org.apache.catalina.tribes.transport.nio.NioReceiver"
address="auto" port="4000" selectorTimeout="100" maxThreads="6" />

<Sender className="org.apache.catalina.tribes.transport.ReplicationTransmitter">
<Transport className="org.apache.catalina.tribes.transport.nio.PooledParallelSender" />
</Sender>

<Interceptor className="org.apache.catalina.tribes.group.interceptors.TcpFailureDetector" />
<Interceptor className="org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor" />
<Interceptor className="org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor" />

</Channel>

<Valve className="org.apache.catalina.ha.tcp.ReplicationValve"
filter=".*\.gif;.*\.js;.*\.jpg;.*\.png;.*\.htm;.*\.html;.*\.css;.*\.txt;" />

<ClusterListener className="org.apache.catalina.ha.session.ClusterSessionListener" />

</Cluster>

<!--For clustering, please take a look at documentation at: /docs/cluster-howto.html
(simple how to) /docs/config/cluster.html (reference documentation) -->
<!-- <Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"/> -->

<!-- Use the LockOutRealm to prevent attempts to guess user passwords
via a brute-force attack -->
<Realm className="org.apache.catalina.realm.LockOutRealm">
<!-- This Realm uses the UserDatabase configured in the global JNDI resources
under the key "UserDatabase". Any edits that are performed against this UserDatabase
are immediately available for use by the Realm. -->
<Realm className="org.apache.catalina.realm.UserDatabaseRealm"
resourceName="UserDatabase" />
</Realm>

<Host appBase="webapps" autoDeploy="true" name="localhost"
unpackWARs="true">

<Context path="/testSession" docBase="D:\EclipseWorkspace2\testSession\WebContent"
reloadable="true" />

<!-- SingleSignOn valve, share authentication between web applications
Documentation at: /docs/config/valve.html -->
<!-- <Valve className="org.apache.catalina.authenticator.SingleSignOn"
/> -->

<!-- Access log processes all example. Documentation at: /docs/config/valve.html
Note: The pattern used is equivalent to using pattern="common" -->
<!-- <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
pattern="%h %l %u %t "%r" %s %b" prefix="localhost_access_log."
suffix=".txt"/> -->
</Host>
</Engine>
</Service>
</Server>

其核心代码如下：

<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"
channelSendOptions="6">

<Manager className="org.apache.catalina.ha.session.BackupManager"
expireSessionsOnShutdown="false" notifyListenersOnReplication="true"
mapSendOptions="6" />

<Channel className="org.apache.catalina.tribes.group.GroupChannel">

<Membership className="org.apache.catalina.tribes.membership.McastService"
address="228.0.0.4" port="45564" frequency="500" dropTime="3000" />

<Receiver className="org.apache.catalina.tribes.transport.nio.NioReceiver"
address="auto" port="4001" selectorTimeout="100" maxThreads="6" />

<Sender className="org.apache.catalina.tribes.transport.ReplicationTransmitter">
<Transport className="org.apache.catalina.tribes.transport.nio.PooledParallelSender" />
</Sender>

<Interceptor className="org.apache.catalina.tribes.group.interceptors.TcpFailureDetector" />
<Interceptor className="org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor" />
<Interceptor className="org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor" />

</Channel>

<Valve className="org.apache.catalina.ha.tcp.ReplicationValve"
filter=".*\.gif;.*\.js;.*\.jpg;.*\.png;.*\.htm;.*\.html;.*\.css;.*\.txt;" />

<ClusterListener className="org.apache.catalina.ha.session.ClusterSessionListener" />

</Cluster>

新建一个简单的web工程，里面只有一个jsp文件，用于测试session。

test.jsp代码如下：

<%@ page language="java" contentType="text/html; charset=utf-8"%>
<%@ page import="java.util.*"%>

<!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>Insert title here</title>
</head>
<body>

<%
out.println("<br> ID " + session.getId() + "<br/>");
String dataName = request.getParameter("dataName");

if (dataName != null && dataName.length() > 0) {
String dataValue = request.getParameter("dataValue");
session.setAttribute(dataName, dataValue);
}

out.print("<b>Session 列表</b><br/>");
Enumeration e = session.getAttributeNames();

while (e.hasMoreElements()) {
String name = (String) e.nextElement();
String value = session.getAttribute(name).toString();
out.println(name + " = " + value + "<br/>");
System.out.println(name + " = " + value);
}
%>
<form action="test.jsp" method="POST">
名称:<input type=text size=20 name="dataName"> <br /> 值:<input
type=text size=20 name="dataValue"> <br /> <input
type=submit value="提交">
</form>
</body>
</html>

其中web.xml代码如下：

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0">

<distributable/>
</web-app>

将该web打包，分别部署在两个tomcat目录下。

在浏览器中输入
http://localhost:8686/testSession/test.jsp http://localhost:8080/testSession/test.jsp
分别在不同的页面设置session，即在另外一个页面可以看到该session值。