说明：这种方式应该算是最通用的，原理是通过判断标签实现。
<!-- if-then form -->
<if condition="some conditional expression">
<then>
...
</then>
</if> <!-- if-then-else form -->
<if condition="some conditional expression">
<then>
...
</then>
<else>
...
</else>
</if>
不过判断条件需要依赖Janino library
<configuration debug="true">
<if condition='property("HOSTNAME").contains("torino")'>
<then>
<appender name="CON" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>%d %-5level %logger{35} - %msg %n</pattern>
</encoder>
</appender>
<root>
<appender-ref ref="CON" />
</root>
</then>
</if>
<appender name="FILE" class="ch.qos.logback.core.FileAppender">
<file>${randomOutputDir}/conditional.log</file>
<encoder>
<pattern>%d %-5level %logger{35} - %msg %n</pattern>
</encoder>
</appender>
<root level="ERROR">
<appender-ref ref="FILE" />
</root>
</configuration>
参考：
https://logback.qos.ch/manual/configuration.html#conditional（官方参考文档）