The Apache Tomcat Servlet/JSP Container

Apache Tomcat 6.0

Version 6.0.51, Mar 9 2017
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Apache Tomcat Configuration Reference

The ClusterManager object

Table of Contents
Introduction

A cluster manager is an extension to Tomcat's session manager interface, org.apache.catalina.Manager. A cluster manager must implement the org.apache.catalina.ha.ClusterManager and is solely responsible for how the session is replicated.
There are currently two different managers, the org.apache.catalina.ha.session.DeltaManager replicates deltas of session data to all members in the cluster. This implementation is proven and works very well, but has a limitation as it requires the cluster members to be homogeneous, all nodes must deploy the same applications and be exact replicas. The org.apache.catalina.ha.session.BackupManager also replicates deltas but only to one backup node. The location of the backup node is known to all nodes in the cluster. It also supports heterogeneous deployments, so the manager knows at what locations the web application is deployed.

The <Manager>

The <Manager> element defined inside the <Cluster> element is the template defined for all web applications that are marked <distributable/> in their web.xml file. However, you can still override the manager implementation on a per web application basis, by putting the <Manager> inside the <Context> element either in the context.xml file or the server.xml file.

Attributes
Common Attributes
AttributeDescription
className
name The name of this cluster manager, the name is used to identify a session manager on a node. The name might get modified by the Cluster element to make it unique in the container.
defaultMode Deprecated since 6.0.0
notifyListenersOnReplication Set to true if you wish to have session listeners notified when session attributes are being replicated or removed across Tomcat nodes in the cluster.
expireSessionsOnShutdown When a web application is being shutdown, Tomcat issues an expire call to each session to notify all the listeners. If you wish for all sessions to expire on all nodes when a shutdown occurs on one node, set this value to true. Default value is false.
org.apache.catalina.ha.session.DeltaManager Attributes
AttributeDescription
domainReplication Deprecated since 6.0.0
If you wish sessions to be replicated only to members that have the same logical domain set, use DomainFilterInterceptor .
expireSessionsOnShutdown When a web application is being shutdown, Tomcat issues an expire call to each session to notify all the listeners. If you wish for all sessions to expire on all nodes when a shutdown occurs on one node, set this value to true. Default value is false.
maxActiveSessions The maximum number of active sessions that will be created by this Manager, or -1 (the default) for no limit. For this manager, all sessions are counted as active sessions irrespective if whether or not the current node is the primary node for the session.
notifySessionListenersOnReplication Set to true if you wish to have session listeners notified when sessions are created and expired across Tomcat nodes in the cluster.
notifyContainerListenersOnReplication Set to true if you wish to have container listeners notified across Tomcat nodes in the cluster.
stateTransferTimeout The time in seconds to wait for a session state transfer to complete from another node when a node is starting up. Default value is 60 seconds.
sessionAttributeNameFilter

A regular expression used to filter which session attributes will be replicated. An attribute will only be replicated if its name matches this pattern. If the pattern is zero length or null, all attributes are eligible for replication. The pattern is anchored so the session attribute name must fully match the pattern. As an example, the value (userName|sessionHistory) will only replicate the two session attributes named userName and sessionHistory. If not specified, the default value of null will be used.

sessionAttributeValueClassNameFilter

A regular expression used to filter which session attributes will be replicated. An attribute will only be replicated if the implementation class name of the value matches this pattern. If the pattern is zero length or null, all attributes are eligible for replication. The pattern is anchored so the fully qualified class name must fully match the pattern. If not specified, the default value of null will be used unless a SecurityManager is enabled in which case the default will be java\\.lang\\.(?:Boolean|Integer|Long|Number|String).

warnOnSessionAttributeFilterFailure

If sessionAttributeNameFilter or sessionAttributeValueClassNameFilter blocks an attribute, should this be logged at WARN level? If WARN level logging is disabled then it will be logged at DEBUG. The default value of this attribute is false unless a SecurityManager is enabled in which case the default will be true.

org.apache.catalina.ha.session.BackupManager Attributes
AttributeDescription
mapSendOptions The backup manager uses a replicated map, this map is sending and receiving messages. You can setup the flag for how this map is sending messages, the default value is 6(synchronous).
Note that if you use asynchronous messaging it is possible for update messages for a session to be processed by the receiving node in a different order to the order in which they were sent.
maxActiveSessions The maximum number of active sessions that will be created by this Manager, or -1 (the default) for no limit. For this manager, only sessions where the current node is the primary node for the session are considered active sessions.
rpcTimeout Timeout for RPC message used for broadcast and transfer state from another map. Default value is 15000 milliseconds.
sessionAttributeNameFilter

A regular expression used to filter which session attributes will be replicated. An attribute will only be replicated if its name matches this pattern. If the pattern is zero length or null, all attributes are eligible for replication. The pattern is anchored so the session attribute name must fully match the pattern. As an example, the value (userName|sessionHistory) will only replicate the two session attributes named userName and sessionHistory. If not specified, the default value of null will be used.

sessionAttributeValueClassNameFilter

A regular expression used to filter which session attributes will be replicated. An attribute will only be replicated if the implementation class name of the value matches this pattern. If the pattern is zero length or null, all attributes are eligible for replication. The pattern is anchored so the fully qualified class name must fully match the pattern. If not specified, the default value of null will be used unless a SecurityManager is enabled in which case the default will be java\\.lang\\.(?:Boolean|Integer|Long|Number|String).

warnOnSessionAttributeFilterFailure

If sessionAttributeNameFilter or sessionAttributeValueClassNameFilter blocks an attribute, should this be logged at WARN level? If WARN level logging is disabled then it will be logged at DEBUG. The default value of this attribute is false unless a SecurityManager is enabled in which case the default will be true.


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