1<?xml version="1.0" encoding="UTF-8" standalone="no"?> 2<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3<html xmlns="http://www.w3.org/1999/xhtml"> 4 <head> 5 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> 6 <title>Replication environment IDs</title> 7 <link rel="stylesheet" href="gettingStarted.css" type="text/css" /> 8 <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> 9 <link rel="start" href="index.html" title="Berkeley DB Programmer's Reference Guide" /> 10 <link rel="up" href="rep.html" title="Chapter��12.�� Berkeley DB Replication" /> 11 <link rel="prev" href="rep.html" title="Chapter��12.�� Berkeley DB Replication" /> 12 <link rel="next" href="rep_pri.html" title="Replication environment priorities" /> 13 </head> 14 <body> 15 <div class="navheader"> 16 <table width="100%" summary="Navigation header"> 17 <tr> 18 <th colspan="3" align="center">Replication environment IDs</th> 19 </tr> 20 <tr> 21 <td width="20%" align="left"><a accesskey="p" href="rep.html">Prev</a>��</td> 22 <th width="60%" align="center">Chapter��12.�� 23 Berkeley DB Replication 24 </th> 25 <td width="20%" align="right">��<a accesskey="n" href="rep_pri.html">Next</a></td> 26 </tr> 27 </table> 28 <hr /> 29 </div> 30 <div class="sect1" lang="en" xml:lang="en"> 31 <div class="titlepage"> 32 <div> 33 <div> 34 <h2 class="title" style="clear: both"><a id="rep_id"></a>Replication environment IDs</h2> 35 </div> 36 </div> 37 </div> 38 <p>Each database environment included in a replication group must have a 39unique identifier for itself and for the other members of the 40replication group. The identifiers do not need to be global, that is, 41each database environment can assign local identifiers to members of 42the replication group as it encounters them. For example, given three 43sites: A, B and C, site A might assign the identifiers 1 and 2 to sites 44B and C respectively, while site B might assign the identifiers 301 and 45302 to sites A and C respectively. Note that it is not wrong to have 46global identifiers, it is just not a requirement.</p> 47 <p> 48 Replication Manager assigns and manages environment IDs on behalf of 49 the application. 50</p> 51 <p>It is the responsibility of a Base API application to label each incoming 52replication message passed to <a href="../api_reference/C/repmessage.html" class="olink">DB_ENV->rep_process_message()</a> method with the appropriate 53identifier. Subsequently, Berkeley DB will label outgoing messages to the 54<span class="bold"><strong>send</strong></span> function with those same identifiers.</p> 55 <p>Negative identifiers are reserved for use by Berkeley DB, and should never be 56assigned to environments by the application. Two of these reserved 57identifiers are intended for application use, as follows:</p> 58 <div class="variablelist"> 59 <dl> 60 <dt> 61 <span class="term"> 62 <a href="../api_reference/C/reptransport.html#transport_DB_EID_BROADCAST" class="olink">DB_EID_BROADCAST</a> 63 </span> 64 </dt> 65 <dd> 66 <p> 67 The <a href="../api_reference/C/reptransport.html#transport_DB_EID_BROADCAST" class="olink">DB_EID_BROADCAST</a> identifier indicates a message should be 68 broadcast to all members of a replication group. 69 </p> 70 </dd> 71 <dt> 72 <a id="rep_id.DB_EID_INVALID"></a> 73 <span class="term">DB_EID_INVALID</span> 74 </dt> 75 <dd> 76 <p> 77 The DB_EID_INVALID identifier is an invalid environment ID, 78 and may be used to initialize environment ID variables that 79 are subsequently checked for validity. 80 </p> 81 </dd> 82 </dl> 83 </div> 84 </div> 85 <div class="navfooter"> 86 <hr /> 87 <table width="100%" summary="Navigation footer"> 88 <tr> 89 <td width="40%" align="left"><a accesskey="p" href="rep.html">Prev</a>��</td> 90 <td width="20%" align="center"> 91 <a accesskey="u" href="rep.html">Up</a> 92 </td> 93 <td width="40%" align="right">��<a accesskey="n" href="rep_pri.html">Next</a></td> 94 </tr> 95 <tr> 96 <td width="40%" align="left" valign="top">Chapter��12.�� 97 Berkeley DB Replication 98 ��</td> 99 <td width="20%" align="center"> 100 <a accesskey="h" href="index.html">Home</a> 101 </td> 102 <td width="40%" align="right" valign="top">��Replication environment priorities</td> 103 </tr> 104 </table> 105 </div> 106 </body> 107</html> 108