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[#forwardingappender]
= ForwardingAppender

The `ForwardingAppender` forwards log messages to another appender.
This appender is used only in special circumstances.

The following example shows how to configure the `ForwardingAppender`.
The forwarding appender allows a set of constraints to be used to decorate an appender.

In this example the `ConsoleAppender` is decorated with a Threshold of level WARN. This means that an event directed to the `ConsoleAppender` directly will be logged regardless of its level, but an event directed to the `ForwardingAppender` will only be passed on to the `ConsoleAppender` if its level is WARN or higher.

[source,xml]
----
<appender name="ForwardingAppender" type="log4net.Appender.ForwardingAppender" >
  <threshold value="WARN"/>
  <appender-ref ref="ConsoleAppender" />
</appender>
----