mirror of
https://github.com/yasuhirokimura/db18
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Yasuhiro KIMURA
210 lines
9.5 KiB
HTML
210 lines
9.5 KiB
HTML
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml">
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
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<title>Base API methods</title>
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<link rel="stylesheet" href="gettingStarted.css" type="text/css" />
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<meta name="generator" content="DocBook XSL Stylesheets V1.73.2" />
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<link rel="start" href="index.html" title="Berkeley DB Programmer's Reference Guide" />
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<link rel="up" href="rep.html" title="Chapter 12. Berkeley DB Replication" />
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<link rel="prev" href="rep_mgr_meth.html" title="Replication Manager methods" />
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<link rel="next" href="rep_comm.html" title="Building the communications infrastructure" />
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</head>
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<body>
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<div xmlns="" class="navheader">
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<div class="libver">
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<p>Library Version 18.1.40</p>
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</div>
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<table width="100%" summary="Navigation header">
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<tr>
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<th colspan="3" align="center">Base API methods</th>
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</tr>
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<tr>
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<td width="20%" align="left"><a accesskey="p" href="rep_mgr_meth.html">Prev</a> </td>
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<th width="60%" align="center">Chapter 12. Berkeley DB Replication </th>
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<td width="20%" align="right"> <a accesskey="n" href="rep_comm.html">Next</a></td>
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</tr>
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</table>
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<hr />
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</div>
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<div class="sect1" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h2 class="title" style="clear: both"><a id="rep_base_meth"></a>Base API methods</h2>
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</div>
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</div>
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</div>
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<p>
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Base API applications use the following Berkeley DB
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methods.
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</p>
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<div class="variablelist">
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<dl>
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<dt>
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<span class="term">
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<a href="../api_reference/C/reptransport.html" class="olink">DB_ENV->rep_set_transport()</a>
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</span>
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</dt>
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<dd>
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<p>
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The <a href="../api_reference/C/reptransport.html" class="olink">DB_ENV->rep_set_transport()</a> method configures the
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replication system's communications
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infrastructure.
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</p>
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</dd>
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<dt>
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<span class="term">
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<a href="../api_reference/C/repstart.html" class="olink">DB_ENV->rep_start()</a>
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</span>
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</dt>
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<dd>
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<p>
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The <a href="../api_reference/C/repstart.html" class="olink">DB_ENV->rep_start()</a> method configures (or
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reconfigures) an existing database environment to
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be a replication master or client.
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</p>
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</dd>
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<dt>
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<span class="term">
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<a href="../api_reference/C/repmessage.html" class="olink">DB_ENV->rep_process_message()</a>
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</span>
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</dt>
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<dd>
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<p>
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The <a href="../api_reference/C/repmessage.html" class="olink">DB_ENV->rep_process_message()</a> method is used to process
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incoming messages from other environments in the
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replication group. For clients, it is responsible
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for accepting log records and updating the local
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databases based on messages from the master. For
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both the master and the clients, it is responsible
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for handling administrative functions (for
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example, the protocol for dealing with lost
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messages), and permitting new clients to join an
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active replication group. This method should only
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be called after the replication system's
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communications infrastructure has been configured
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via <a href="../api_reference/C/reptransport.html" class="olink">DB_ENV->rep_set_transport()</a>.
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</p>
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</dd>
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<dt>
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<span class="term">
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<a href="../api_reference/C/repelect.html" class="olink">DB_ENV->rep_elect()</a>
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</span>
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</dt>
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<dd>
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<p>
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The <a href="../api_reference/C/repelect.html" class="olink">DB_ENV->rep_elect()</a> method causes the replication
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group to elect a new master; it is called whenever
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contact with the master is lost and the
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application wants the remaining sites to select a
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new master.
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</p>
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</dd>
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<dt>
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<span class="term">
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<a href="../api_reference/C/envevent_notify.html" class="olink">DB_ENV->set_event_notify()</a>
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</span>
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</dt>
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<dd>
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<p>
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The <a href="../api_reference/C/envevent_notify.html" class="olink">DB_ENV->set_event_notify()</a> method is needed for
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applications to discover important
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replication-related events, such as the result of
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an election and appointment of a new master.
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</p>
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</dd>
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<dt>
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<span class="term">
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<a href="../api_reference/C/reppriority.html" class="olink">DB_ENV->rep_set_priority()</a>
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</span>
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</dt>
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<dd>
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<p>
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The <a href="../api_reference/C/reppriority.html" class="olink">DB_ENV->rep_set_priority()</a> method configures the local
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site's priority for the purpose of elections.
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</p>
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</dd>
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<dt>
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<span class="term">
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<a href="../api_reference/C/repset_timeout.html" class="olink">DB_ENV->rep_set_timeout()</a>
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</span>
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</dt>
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<dd>
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<p>
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This method optionally configures various
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timeout values. Otherwise default timeout values
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as specified in <a href="../api_reference/C/repset_timeout.html" class="olink">DB_ENV->rep_set_timeout()</a> are used.
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</p>
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</dd>
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<dt>
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<span class="term">
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<a href="../api_reference/C/repset_limit.html" class="olink">DB_ENV->rep_set_limit()</a>
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</span>
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</dt>
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<dd>
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<p>
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The <a href="../api_reference/C/repset_limit.html" class="olink">DB_ENV->rep_set_limit()</a> method imposes an upper bound on
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the amount of data that will be sent in response
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to a single call to <a href="../api_reference/C/repmessage.html" class="olink">DB_ENV->rep_process_message()</a>. During client
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recovery, that is, when a replica site is trying
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to synchronize with the master, clients may ask
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the master for a large number of log records. If
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it is going to harm an application for the master
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message loop to remain busy for an extended period
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transmitting records to the replica, then the
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application will want to use <a href="../api_reference/C/repset_limit.html" class="olink">DB_ENV->rep_set_limit()</a> to limit
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the amount of data the master will send before
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relinquishing control and accepting other
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messages.
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</p>
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</dd>
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<dt>
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<span class="term">
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<a href="../api_reference/C/repset_request.html" class="olink">DB_ENV->rep_set_request()</a>
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</span>
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</dt>
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<dd>
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<p>
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This method sets a threshold for the minimum
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and maximum time that a client waits before
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requesting retransmission of a missing message.
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</p>
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</dd>
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</dl>
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</div>
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<p>
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Base API applications may configure one or more view sites.
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A view is a full or partial copy of the replicated data that
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does not otherwise participate in the replication group. For
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more information, see <a class="xref" href="rep_partview.html" title="Replication views">Replication views</a>.
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</p>
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<p>
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In addition to the methods previously described, Base API
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applications may also call the following methods, as needed:
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<a href="../api_reference/C/repstat.html" class="olink">DB_ENV->rep_stat()</a>, <a href="../api_reference/C/repsync.html" class="olink">DB_ENV->rep_sync()</a> and <a href="../api_reference/C/repconfig.html" class="olink">DB_ENV->rep_set_config()</a>
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</p>
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</div>
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<div class="navfooter">
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<hr />
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<table width="100%" summary="Navigation footer">
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||
<tr>
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||
<td width="40%" align="left"><a accesskey="p" href="rep_mgr_meth.html">Prev</a> </td>
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<td width="20%" align="center">
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<a accesskey="u" href="rep.html">Up</a>
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</td>
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<td width="40%" align="right"> <a accesskey="n" href="rep_comm.html">Next</a></td>
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</tr>
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<tr>
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<td width="40%" align="left" valign="top">Replication Manager methods </td>
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<td width="20%" align="center">
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<a accesskey="h" href="index.html">Home</a>
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</td>
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<td width="40%" align="right" valign="top"> Building the communications infrastructure</td>
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</tr>
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</table>
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</div>
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</body>
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</html>
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