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| <ul><li><a href="#Introduction">Introduction</a></li><li><a href="#Nested_Components">Nested Components</a></li><li><a href="#Attributes">Attributes</a><ol><li><a href="#Common_Attributes">Common Attributes</a></li><li><a href="#org.apache.catalina.tribes.group.GroupChannel_Attributes">org.apache.catalina.tribes.group.GroupChannel Attributes</a></li></ol></li></ul> | |
| </blockquote></td></tr></table><table border="0" cellspacing="0" cellpadding="2"><tr><td bgcolor="#525D76"><font color="#ffffff" face="arial,helvetica.sanserif"><a name="Introduction"><strong>Introduction</strong></a></font></td></tr><tr><td><blockquote> | |
| The cluster channel is the main component of a small framework we've nicknamed Apache Tribes.<br> | |
| The channel manages a set of sub components and together they create a group communication framework.<br> | |
| This framework is then used internally by the components that need to send messages between different Tomcat instances. | |
| <br> | |
| A few examples of these components would be the SimpleTcpCluster that does the messaging for the DeltaManager, | |
| or the BackupManager that uses a different replication strategy. The ReplicatedContext object does also | |
| use the channel object to communicate context attribute changes. | |
| </blockquote></td></tr></table><table border="0" cellspacing="0" cellpadding="2"><tr><td bgcolor="#525D76"><font color="#ffffff" face="arial,helvetica.sanserif"><a name="Nested Components"><!--()--></a><a name="Nested_Components"><strong>Nested Components</strong></a></font></td></tr><tr><td><blockquote> | |
| <p><b><a href="cluster-membership.html">Channel/Membership</a>:</b> <br> | |
| The Membership component is responsible for auto discovering new nodes in the cluster | |
| and also to provide for notifications for any nodes that have not responded with a heartbeat. | |
| The default implementation uses multicast.<br> | |
| In the membership component you configure how your nodes, aka. members, are to be discovered and/or | |
| divided up. | |
| You can always find out more about <a href="../tribes/introduction.html">Apache Tribes</a> | |
| </p> | |
| <p><b><a href="cluster-sender.html">Channel/Sender</a>:</b> <br> | |
| The Sender component manages all outbound connections and data messages that are sent | |
| over the network from one node to another. | |
| This component allows messages to be sent in parallel. | |
| The default implementation uses TCP client sockets, and socket tuning for outgoing messages are | |
| configured here.<br> | |
| You can always find out more about <a href="../tribes/introduction.html">Apache Tribes</a> | |
| </p> | |
| <p><b><a href="cluster-sender.html#transport">Channel/Sender/Transport</a>:</b> <br> | |
| The Transport component is the bottom IO layer for the sender component. | |
| The default implementation uses non-blocking TCP client sockets.<br> | |
| You can always find out more about <a href="../tribes/introduction.html">Apache Tribes</a> | |
| </p> | |
| <p><b><a href="cluster-receiver.html">Channel/Receiver</a>:</b> <br> | |
| The receiver component listens for messages from other nodes. | |
| Here you will configure the cluster thread pool, as it will dispatch incoming | |
| messages to a thread pool for faster processing. | |
| The default implementation uses non-blocking TCP server sockets.<br> | |
| You can always find out more about <a href="../tribes/introduction.html">Apache Tribes</a> | |
| </p> | |
| <p><b><a href="cluster-interceptor.html">Channel/Interceptor</a>:</b> <br> | |
| The channel will send messages through an interceptor stack. Because of this, you have the ability to | |
| customize the way messages are sent and received, and even how membership is handled.<br> | |
| You can always find out more about <a href="../tribes/introduction.html">Apache Tribes</a> | |
| </p> | |
| </blockquote></td></tr></table><table border="0" cellspacing="0" cellpadding="2"><tr><td bgcolor="#525D76"><font color="#ffffff" face="arial,helvetica.sanserif"><a name="Attributes"><strong>Attributes</strong></a></font></td></tr><tr><td><blockquote> | |
| <table border="0" cellspacing="0" cellpadding="2"><tr><td bgcolor="#828DA6"><font color="#ffffff" face="arial,helvetica.sanserif"><a name="Common Attributes"><!--()--></a><a name="Common_Attributes"><strong>Common Attributes</strong></a></font></td></tr><tr><td><blockquote> | |
| <table border="1" cellpadding="5"><tr><th width="15%" bgcolor="#023264"><font color="#ffffff">Attribute</font></th><th width="85%" bgcolor="#023264"><font color="#ffffff">Description</font></th></tr><tr><td align="left" valign="center"><strong><code class="attributeName">className</code></strong></td><td align="left" valign="center"> | |
| The default value here is <code>org.apache.catalina.tribes.group.GroupChannel</code> and is | |
| currently the only implementation available. | |
| </td></tr></table> | |
| </blockquote></td></tr></table> | |
| <table border="0" cellspacing="0" cellpadding="2"><tr><td bgcolor="#828DA6"><font color="#ffffff" face="arial,helvetica.sanserif"><a name="org.apache.catalina.tribes.group.GroupChannel Attributes"><!--()--></a><a name="org.apache.catalina.tribes.group.GroupChannel_Attributes"><strong>org.apache.catalina.tribes.group.GroupChannel Attributes</strong></a></font></td></tr><tr><td><blockquote> | |
| <table border="1" cellpadding="5"><tr><th width="15%" bgcolor="#023264"><font color="#ffffff">Attribute</font></th><th width="85%" bgcolor="#023264"><font color="#ffffff">Description</font></th></tr><tr><td align="left" valign="center"><code class="attributeName">heartbeat</code></td><td align="left" valign="center"> | |
| Flag whether the channel manages its own heartbeat. | |
| If set to true, the channel start a local thread for the heart beat. | |
| If set this flag to false, you must set SimpleTcpCluster#heartbeatBackgroundEnabled | |
| to true. default value is true. | |
| </td></tr><tr><td align="left" valign="center"><code class="attributeName">heartbeatSleeptime</code></td><td align="left" valign="center"> | |
| If heartbeat == true, specifies the interval of heartbeat thread in milliseconds. | |
| The default is 5000 (5 seconds). | |
| </td></tr><tr><td align="left" valign="center"><code class="attributeName">optionCheck</code></td><td align="left" valign="center"> | |
| If set to true, the GroupChannel will check the option flags that each | |
| interceptor is using. Reports an error if two interceptor share the same | |
| flag. The default is false. | |
| </td></tr></table> | |
| </blockquote></td></tr></table> | |
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