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<div class="sect1" lang="en" xml:lang="en">
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<div>
<h2 class="title" style="clear: both"><a id="reppriority"></a>DB_ENV->rep_set_priority()</h2>
</div>
</div>
</div>
<pre class="programlisting">#include <db.h>
int
DB_ENV->rep_set_priority(DB_ENV *env, u_int32_t priority); </pre>
<p>
The <code class="methodname">DB_ENV->rep_set_priority()</code> method specifies the database
environment's priority in replication group elections. A special
value of 0 indicates that this environment cannot be a replication
group master.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
The
<a class="xref" href="repmgrset_ack_policy.html" title="DB_ENV->repmgr_set_ack_policy()">DB_ENV->repmgr_set_ack_policy()</a>
method describes <span class="emphasis"><em>electable peers</em></span>, which
are replication sites with a non-zero priority. For some
acknowledgement policies, Replication Manager's computation of
the durability result for each new update transaction is
sensitive to whether each site in the group is a peer.
Therefore, if you change a site's priority from a non-zero
value to <code class="literal">0</code>, or from <code class="literal">0</code> to
a non-zero value, this can invalidate the durability result of
previously committed transactions.
</p>
</div>
<p>
The database environment's replication subsystem may also be
configured using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The syntax
of the entry in that file is a single line with the string
"rep_set_priority", one or more whitespace characters, and the
priority of this site. For example, "rep_set_priority 1" sets the
priority of this site to 1. Because the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read
when the database environment is opened, it will silently overrule
configuration done before that time.
</p>
<p>
Note that if the application never explicitly sets a priority, then
a default value of 100 is used. In preferred master mode, priority
values for each site are automatically set and any attempt to change
them results in an error.
</p>
<p>
The <code class="methodname">DB_ENV->rep_set_priority()</code> method configures a database
environment, not only operations performed using the specified
<a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a> handle.
</p>
<p>
The <code class="methodname">DB_ENV->rep_set_priority()</code> method may be called at any time
during the life of the application.
</p>
<p>
The <code class="methodname">DB_ENV->rep_set_priority()</code> <span>
<span>
method returns a non-zero error value on failure and 0 on success.
</span>
</span>
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp3832648"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp3832000"></a>priority</h4>
</div>
</div>
</div>
<p>
The priority of this database environment in the replication group. The
priority must be a non-zero integer, or 0 if this environment cannot be a
replication group master. (See
<a href="../../programmer_reference/rep_pri.html" class="olink">Replication environment priorities</a>
for more information).
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp3813440"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DB_ENV->rep_set_priority()</code> <span>
<span>
method may fail and return one of the following non-zero errors:
</span>
</span>
</p>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp3841632"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
If changing the automatically set priority value in
Replication Manager preferred master mode.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp3836176"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp3831760"></a>See Also</h3>
</div>
</div>
</div>
<p>
<a class="xref" href="rep.html#replist" title="Replication and Related Methods">Replication and Related Methods</a>
</p>
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