<div id="docs-body">
 <div class="section">
  <div class="titlepage">
   <div>
    <div>
     <h4 class="title">
      <a name="connection-control-variables">
      </a>
      8.4.2.2 Connection-Control System and Status Variables
     </h4>
    </div>
   </div>
  </div>
  <p>
   This section describes the system and status variables that the
   <code class="literal">
    CONNECTION_CONTROL
   </code>
   plugin provides to enable
        its operation to be configured and monitored.
  </p>
  <div class="itemizedlist">
   <ul class="itemizedlist" style="list-style-type: disc; ">
    <li class="listitem">
     <p>
      <a class="xref" href="connection-control-variables.html#connection-control-plugin-system-variables" title="Connection-Control System Variables">
       Connection-Control System Variables
      </a>
     </p>
    </li>
    <li class="listitem">
     <p>
      <a class="xref" href="connection-control-variables.html#connection-control-plugin-status-variables" title="Connection-Control Status Variables">
       Connection-Control Status Variables
      </a>
     </p>
    </li>
   </ul>
  </div>
  <div class="simplesect">
   <div class="titlepage">
    <div>
     <div class="simple">
      <h5 class="title">
       <a name="connection-control-plugin-system-variables">
       </a>
       Connection-Control System Variables
      </h5>
     </div>
    </div>
   </div>
   <a class="indexterm" name="idm46045241965792">
   </a>
   <p>
    If the
    <code class="literal">
     CONNECTION_CONTROL
    </code>
    plugin is
          installed, it exposes these system variables:
   </p>
   <div class="itemizedlist">
    <ul class="itemizedlist" style="list-style-type: disc; ">
     <li class="listitem">
      <p>
       <a name="sysvar_connection_control_failed_connections_threshold">
       </a>
       <a class="link" href="connection-control-variables.html#sysvar_connection_control_failed_connections_threshold">
        <code class="literal">
         connection_control_failed_connections_threshold
        </code>
       </a>
      </p>
      <a class="indexterm" name="idm46045241960464">
      </a>
      <a class="indexterm" name="idm46045241959424">
      </a>
      <div class="informaltable">
       <table frame="box" rules="all" summary="Properties for connection_control_failed_connections_threshold">
        <colgroup>
         <col style="width: 30%"/>
         <col style="width: 70%"/>
        </colgroup>
        <tbody>
         <tr>
          <th>
           Command-Line Format
          </th>
          <td>
           <code class="literal">
            --connection-control-failed-connections-threshold=#
           </code>
          </td>
         </tr>
         <tr>
          <th>
           System Variable
          </th>
          <td>
           <code class="literal">
            <a class="link" href="connection-control-variables.html#sysvar_connection_control_failed_connections_threshold">
             connection_control_failed_connections_threshold
            </a>
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Scope
          </th>
          <td>
           Global
          </td>
         </tr>
         <tr>
          <th>
           Dynamic
          </th>
          <td>
           Yes
          </td>
         </tr>
         <tr>
          <th>
           <a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
            <code class="literal">
             SET_VAR
            </code>
           </a>
           Hint Applies
          </th>
          <td>
           No
          </td>
         </tr>
         <tr>
          <th>
           Type
          </th>
          <td>
           Integer
          </td>
         </tr>
         <tr>
          <th>
           Default Value
          </th>
          <td>
           <code class="literal">
            3
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Minimum Value
          </th>
          <td>
           <code class="literal">
            0
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Maximum Value
          </th>
          <td>
           <code class="literal">
            2147483647
           </code>
          </td>
         </tr>
        </tbody>
       </table>
      </div>
      <p>
       The number of consecutive failed connection attempts
              permitted to accounts before the server adds a delay for
              subsequent connection attempts:
      </p>
      <div class="itemizedlist">
       <ul class="itemizedlist" style="list-style-type: circle; ">
        <li class="listitem">
         <p>
          If the variable has a nonzero value
          <em class="replaceable">
           <code>
            N
           </code>
          </em>
          , the server adds a delay
                  beginning with consecutive failed attempt
          <em class="replaceable">
           <code>
            N
           </code>
          </em>
          +1. If an account has
                  reached the point where connection responses are
                  delayed, a delay also occurs for the next subsequent
                  successful connection.
         </p>
        </li>
        <li class="listitem">
         <p>
          Setting this variable to zero disables
                  failed-connection counting. In this case, the server
                  never adds delays.
         </p>
        </li>
       </ul>
      </div>
      <p>
       For information about how
       <a class="link" href="connection-control-variables.html#sysvar_connection_control_failed_connections_threshold">
        <code class="literal">
         connection_control_failed_connections_threshold
        </code>
       </a>
       interacts with other connection-control system and status
              variables, see
       <a class="xref" href="connection-control-installation.html" title="8.4.2.1 Connection-Control Plugin Installation">
        Section 8.4.2.1, “Connection-Control Plugin Installation”
       </a>
       .
      </p>
     </li>
     <li class="listitem">
      <p>
       <a name="sysvar_connection_control_max_connection_delay">
       </a>
       <a class="link" href="connection-control-variables.html#sysvar_connection_control_max_connection_delay">
        <code class="literal">
         connection_control_max_connection_delay
        </code>
       </a>
      </p>
      <a class="indexterm" name="idm46045241923600">
      </a>
      <a class="indexterm" name="idm46045241922560">
      </a>
      <div class="informaltable">
       <table frame="box" rules="all" summary="Properties for connection_control_max_connection_delay">
        <colgroup>
         <col style="width: 30%"/>
         <col style="width: 70%"/>
        </colgroup>
        <tbody>
         <tr>
          <th>
           Command-Line Format
          </th>
          <td>
           <code class="literal">
            --connection-control-max-connection-delay=#
           </code>
          </td>
         </tr>
         <tr>
          <th>
           System Variable
          </th>
          <td>
           <code class="literal">
            <a class="link" href="connection-control-variables.html#sysvar_connection_control_max_connection_delay">
             connection_control_max_connection_delay
            </a>
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Scope
          </th>
          <td>
           Global
          </td>
         </tr>
         <tr>
          <th>
           Dynamic
          </th>
          <td>
           Yes
          </td>
         </tr>
         <tr>
          <th>
           <a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
            <code class="literal">
             SET_VAR
            </code>
           </a>
           Hint Applies
          </th>
          <td>
           No
          </td>
         </tr>
         <tr>
          <th>
           Type
          </th>
          <td>
           Integer
          </td>
         </tr>
         <tr>
          <th>
           Default Value
          </th>
          <td>
           <code class="literal">
            2147483647
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Minimum Value
          </th>
          <td>
           <code class="literal">
            1000
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Maximum Value
          </th>
          <td>
           <code class="literal">
            2147483647
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Unit
          </th>
          <td>
           milliseconds
          </td>
         </tr>
        </tbody>
       </table>
      </div>
      <p>
       The maximum delay in milliseconds for server response to
              failed connection attempts, if
       <a class="link" href="connection-control-variables.html#sysvar_connection_control_failed_connections_threshold">
        <code class="literal">
         connection_control_failed_connections_threshold
        </code>
       </a>
       is greater than zero.
      </p>
      <p>
       For information about how
       <a class="link" href="connection-control-variables.html#sysvar_connection_control_max_connection_delay">
        <code class="literal">
         connection_control_max_connection_delay
        </code>
       </a>
       interacts with other connection-control system and status
              variables, see
       <a class="xref" href="connection-control-installation.html" title="8.4.2.1 Connection-Control Plugin Installation">
        Section 8.4.2.1, “Connection-Control Plugin Installation”
       </a>
       .
      </p>
     </li>
     <li class="listitem">
      <p>
       <a name="sysvar_connection_control_min_connection_delay">
       </a>
       <a class="link" href="connection-control-variables.html#sysvar_connection_control_min_connection_delay">
        <code class="literal">
         connection_control_min_connection_delay
        </code>
       </a>
      </p>
      <a class="indexterm" name="idm46045241886800">
      </a>
      <a class="indexterm" name="idm46045241885760">
      </a>
      <div class="informaltable">
       <table frame="box" rules="all" summary="Properties for connection_control_min_connection_delay">
        <colgroup>
         <col style="width: 30%"/>
         <col style="width: 70%"/>
        </colgroup>
        <tbody>
         <tr>
          <th>
           Command-Line Format
          </th>
          <td>
           <code class="literal">
            --connection-control-min-connection-delay=#
           </code>
          </td>
         </tr>
         <tr>
          <th>
           System Variable
          </th>
          <td>
           <code class="literal">
            <a class="link" href="connection-control-variables.html#sysvar_connection_control_min_connection_delay">
             connection_control_min_connection_delay
            </a>
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Scope
          </th>
          <td>
           Global
          </td>
         </tr>
         <tr>
          <th>
           Dynamic
          </th>
          <td>
           Yes
          </td>
         </tr>
         <tr>
          <th>
           <a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
            <code class="literal">
             SET_VAR
            </code>
           </a>
           Hint Applies
          </th>
          <td>
           No
          </td>
         </tr>
         <tr>
          <th>
           Type
          </th>
          <td>
           Integer
          </td>
         </tr>
         <tr>
          <th>
           Default Value
          </th>
          <td>
           <code class="literal">
            1000
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Minimum Value
          </th>
          <td>
           <code class="literal">
            1000
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Maximum Value
          </th>
          <td>
           <code class="literal">
            2147483647
           </code>
          </td>
         </tr>
         <tr>
          <th>
           Unit
          </th>
          <td>
           milliseconds
          </td>
         </tr>
        </tbody>
       </table>
      </div>
      <p>
       The minimum delay in milliseconds for server response to
              failed connection attempts, if
       <a class="link" href="connection-control-variables.html#sysvar_connection_control_failed_connections_threshold">
        <code class="literal">
         connection_control_failed_connections_threshold
        </code>
       </a>
       is greater than zero.
      </p>
      <p>
       For information about how
       <a class="link" href="connection-control-variables.html#sysvar_connection_control_min_connection_delay">
        <code class="literal">
         connection_control_min_connection_delay
        </code>
       </a>
       interacts with other connection-control system and status
              variables, see
       <a class="xref" href="connection-control-installation.html" title="8.4.2.1 Connection-Control Plugin Installation">
        Section 8.4.2.1, “Connection-Control Plugin Installation”
       </a>
       .
      </p>
     </li>
    </ul>
   </div>
  </div>
  <div class="simplesect">
   <div class="titlepage">
    <div>
     <div class="simple">
      <h5 class="title">
       <a name="connection-control-plugin-status-variables">
       </a>
       Connection-Control Status Variables
      </h5>
     </div>
    </div>
   </div>
   <a class="indexterm" name="idm46045241850976">
   </a>
   <p>
    If the
    <code class="literal">
     CONNECTION_CONTROL
    </code>
    plugin is
          installed, it exposes this status variable:
   </p>
   <div class="itemizedlist">
    <ul class="itemizedlist" style="list-style-type: disc; ">
     <li class="listitem">
      <p>
       <a name="statvar_Connection_control_delay_generated">
       </a>
       <a class="link" href="connection-control-variables.html#statvar_Connection_control_delay_generated">
        <code class="literal">
         Connection_control_delay_generated
        </code>
       </a>
      </p>
      <a class="indexterm" name="idm46045241845664">
      </a>
      <a class="indexterm" name="idm46045241844624">
      </a>
      <p>
       The number of times the server added a delay to its
              response to a failed connection attempt. This does not
              count attempts that occur before reaching the threshold
              defined by the
       <a class="link" href="connection-control-variables.html#sysvar_connection_control_failed_connections_threshold">
        <code class="literal">
         connection_control_failed_connections_threshold
        </code>
       </a>
       system variable.
      </p>
      <p>
       This variable provides a simple counter. For more detailed
              connection-control monitoring information, examine the
       <code class="literal">
        INFORMATION_SCHEMA
       </code>
       <a class="link" href="information-schema-connection-control-failed-login-attempts-table.html" title="28.6.2 The INFORMATION_SCHEMA CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS Table">
        <code class="literal">
         CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS
        </code>
       </a>
       table; see
       <a class="xref" href="information-schema-connection-control-failed-login-attempts-table.html" title="28.6.2 The INFORMATION_SCHEMA CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS Table">
        Section 28.6.2, “The INFORMATION_SCHEMA CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS Table”
       </a>
       .
      </p>
      <p>
       Assigning a value to
       <a class="link" href="connection-control-variables.html#sysvar_connection_control_failed_connections_threshold">
        <code class="literal">
         connection_control_failed_connections_threshold
        </code>
       </a>
       at runtime resets
       <a class="link" href="connection-control-variables.html#statvar_Connection_control_delay_generated">
        <code class="literal">
         Connection_control_delay_generated
        </code>
       </a>
       to zero.
      </p>
     </li>
    </ul>
   </div>
  </div>
 </div>
 <br/>
</div>
