1<!--$Id: mgr_meth.so,v 1.10 2008/04/23 13:35:47 sue Exp $--> 2<!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> 3<!--See the file LICENSE for redistribution information.--> 4<html> 5<head> 6<title>Berkeley DB Reference Guide: Replication Manager methods</title> 7<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> 8<meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> 9</head> 10<body bgcolor=white> 11<table width="100%"><tr valign=top> 12<td><b><dl><dt>Berkeley DB Reference Guide:<dd>Berkeley DB Replication</dl></b></td> 13<td align=right><a href="../rep/app.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../rep/base_meth.html"><img src="../../images/next.gif" alt="Next"></a> 14</td></tr></table> 15<p align=center><b>Replication Manager methods</b></p> 16<p>Applications which use the Replication Manager support generally call 17the following Berkeley DB methods. The general pattern is to call various 18methods to configure Replication Manager, and then start it by calling 19<a href="../../api_c/repmgr_start.html">DB_ENV->repmgr_start</a>. Once this initialization is complete, the 20application rarely needs to call any of these methods. (A prime 21example of an exception to this rule would be the <a href="../../api_c/rep_sync.html">DB_ENV->rep_sync</a> method, 22if the application is doing <a href="../../ref/rep/mastersync.html">delayed synchronization</a>.)</p> 23<br> 24<b><a href="../../api_c/repmgr_local_site.html">DB_ENV->repmgr_set_local_site</a></b><ul compact><li>The <a href="../../api_c/repmgr_local_site.html">DB_ENV->repmgr_set_local_site</a> method configures the TCP/IP address of 25the local site, by specifying the port number on which it is to listen 26for incoming connection requests. This method must be called exactly 27once before calling <a href="../../api_c/repmgr_start.html">DB_ENV->repmgr_start</a>.</ul> 28<b><a href="../../api_c/repmgr_remote_site.html">DB_ENV->repmgr_add_remote_site</a></b><ul compact><li>The <a href="../../api_c/repmgr_remote_site.html">DB_ENV->repmgr_add_remote_site</a> method adds a remote site to the list of 29sites initially known by the local site. The remote site is specified 30in terms of a TCP/IP network address: host name and port number. This 31method may be called as many times as necessary to configure all known 32remote sites. Note that it is usually not necessary for each site in 33the replication group initially to know about all other sites in the 34group. Sites can discover each other dynamically, as described in 35<a href="../../ref/rep/newsite.html">Connecting to a new site</a>.</ul> 36<b><a href="../../api_c/repmgr_ack_policy.html">DB_ENV->repmgr_set_ack_policy</a></b><ul compact><li>The <a href="../../api_c/repmgr_ack_policy.html">DB_ENV->repmgr_set_ack_policy</a> method configures the acknowledgement 37policy to be used in the replication group, in other words, the 38behavior of the master with respect to acknowledgements for 39"permanent" messages, which implements the application's requirements 40for <a href="../../ref/rep/trans.html">transactional guarantees</a>. The 41current implementation requires all sites in the replication group 42configure the same acknowledgement policy.</ul> 43<b><a href="../../api_c/rep_nsites.html">DB_ENV->rep_set_nsites</a></b><ul compact><li>The <a href="../../api_c/rep_nsites.html">DB_ENV->rep_set_nsites</a> method tells Replication Manager the total number 44of sites in the replication group. This is usually necessary for 45proper operation of elections, and for counting message 46acknowledgements (depending on the acknowledgement policy).</ul> 47<b><a href="../../api_c/rep_priority.html">DB_ENV->rep_set_priority</a></b><ul compact><li>The <a href="../../api_c/rep_priority.html">DB_ENV->rep_set_priority</a> method configures the local site's priority for 48the purpose of elections.</ul> 49<b><a href="../../api_c/rep_timeout.html">DB_ENV->rep_set_timeout</a></b><ul compact><li>This method optionally configures various timeout values. Otherwise 50default timeout values as specified in <a href="../../api_c/rep_timeout.html">DB_ENV->rep_set_timeout</a> are 51used. In particular, Replication Manager client sites can be 52configured to monitor the health of the TCP/IP connection to the 53master site using heartbeat messages. If the client receives no 54messages from the master for a certain amount of time, it considers 55the connection to be broken, and calls for an election to choose a new 56master.</ul> 57<b><a href="../../api_c/env_event_notify.html">DB_ENV->set_event_notify</a></b><ul compact><li>Once configured and started, Replication Manager does virtually all of 58its work in the background, usually without the need for any direct 59communication with the application. However, occasionally events 60occur which the application may be interested in knowing about. The 61application can request notification of these events by calling the 62<a href="../../api_c/env_event_notify.html">DB_ENV->set_event_notify</a> method.</ul> 63<b><a href="../../api_c/repmgr_start.html">DB_ENV->repmgr_start</a></b><ul compact><li>The <a href="../../api_c/repmgr_start.html">DB_ENV->repmgr_start</a> method starts the replication system. It opens the 64listening TCP/IP socket and creates all the background processing 65threads that will be needed.</ul> 66<br> 67<p>In addition to the methods previously described, Replication Manager 68applications may also call the following methods, as needed: 69<a href="../../api_c/rep_config.html">DB_ENV->rep_set_config</a>, <a href="../../api_c/rep_limit.html">DB_ENV->rep_set_limit</a>, <a href="../../api_c/rep_request.html">DB_ENV->rep_set_request</a>, 70<a href="../../api_c/rep_sync.html">DB_ENV->rep_sync</a>, <a href="../../api_c/rep_stat.html">DB_ENV->rep_stat</a>.</p> 71<table width="100%"><tr><td><br></td><td align=right><a href="../rep/app.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../rep/base_meth.html"><img src="../../images/next.gif" alt="Next"></a> 72</td></tr></table> 73<p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> 74</body> 75</html> 76