Only log to ELMAH if there's an exception

[RudeySH]

Can we get an option to only send logs to ELMAH when there's a logged exception to go with it?

[snakefoot]

You can setup a filter, to only perform target-output on exceptions:

<rules>
    <logger name="*" minLevel="Warn" writeTo="elmah">
        <filters>
            <when condition="length('${exception:format=type}') > 0" action="Log" />
        </filters>
    </logger>
</rules>