doc/java-broker/src/docbkx/management/managing/Java-Broker-Management-Managing-RemoteReplicationNodes.xml

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<section xmlns="http://docbook.org/ns/docbook" version="5.0" xml:id="Java-Broker-Management-Managing-RemoteReplicationNodes">
  <title>Remote Replication Nodes</title>
  <para>Used for HA only. A <link linkend="Java-Broker-Concepts-RemoteReplicationNodes">remote replication node</link> is a representation of another virtualhost node
    in the group. Remote replication nodes are not created directly. Instead the system
    automatically creates a remote replication node for every node in the group. It serves to
    provide a view of the whole group from every node in the system.</para>
  <section xml:id="Java-Broker-Management-Managing-RemoteReplicationNodes-Attributes">
    <title>Attributes</title>
    <para><itemizedlist>
        <listitem>
          <para><emphasis>Name the remote replication node</emphasis>. This is the name of the
            remote virtualhost node</para>
        </listitem>
        <listitem>
          <para><emphasis>Role</emphasis>. Indicates the role that the remote node is playing in the
            group at this moment. <itemizedlist>
              <listitem>
                <para><emphasis>MASTER</emphasis> - Remote node is a master.</para>
              </listitem>
              <listitem>
                <para><emphasis>REPLICA</emphasis> - Remote node is a replica.</para>
              </listitem>
              <listitem>
                <para><emphasis>UNREACHABLE</emphasis> - Remote node unreachable from this node.
                  This remote note may be down, or an network problem may prevent it from being
                  contacted.</para>
              </listitem>
            </itemizedlist>
          </para>
        </listitem>
        <listitem>
          <para><emphasis>Join time</emphasis>. Time when first contact was established with this
            node.</para>
        </listitem>
        <listitem>
          <para><emphasis>Last known transaction id</emphasis>. Last transaction id reported
            processed by node. This is an internal transaction counter and does not relate to any
            value available to the messaging clients. This value can only be used to determine the
            node is up to date relative to others in the group.</para>
        </listitem>
      </itemizedlist></para>
  </section>
  <section xml:id="Java-Broker-Management-Managing-RemoteReplicationNodes-Children">
    <title>Children</title>
    <para>None</para>
  </section>
  <section xml:id="Java-Broker-Management-Managing-RemoteReplicationNodes-Lifecycle">
    <title>Lifecycle</title>
    <para>
      <itemizedlist>
        <listitem>
          <para><emphasis>Delete</emphasis>. Causes the remote node to be permanently removed from
            the group. This operation should be used when the virtualhost node cannot be deleted
            from its own Broker, for instance, if a Broker has been destroyed by machine
            failure.</para>
        </listitem>
      </itemizedlist>
    </para>
  </section>
  <section xml:id="Java-Broker-Management-Managing-RemoteReplication-Nodes-Operations">
    <title>Operations</title>
    <para>
      <itemizedlist>
        <listitem>
          <para><emphasis>Transfer Master</emphasis>. Initiates a process where a master is moved to
            anther node in the group. The transfer sequence is as follows. <orderedlist>
              <listitem>
                <para>Group waits until the proposed master is reasonable up to date.</para>
              </listitem>
              <listitem>
                <para>Any in-flight transactions on the current master are blocked.</para>
              </listitem>
              <listitem>
                <para>The current master awaits the proposed master to become up to date.</para>
              </listitem>
              <listitem>
                <para>The mastership is transferred. This will automatically disconnect messaging
                  clients from the old master, and in-flight transactions are rolled back. Messaging
                  clients reconnect to the new master.</para>
              </listitem>
              <listitem>
                <para>The old master will rejoin as a replica.</para>
              </listitem>
            </orderedlist>
          </para>
        </listitem>
      </itemizedlist>
    </para>
  </section>
</section>