flink-dist/src/main/flink-bin/conf/logback.xml

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  ~ to you under the Apache License, Version 2.0 (the
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<configuration>
    <appender name="file" class="ch.qos.logback.core.FileAppender">
        <file>${log.file}</file>
        <append>false</append>
        <encoder>
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{60} %X{sourceThread} - %msg%n</pattern>
        </encoder>
    </appender>

    <!-- This affects logging for both user code and Flink -->
    <root level="INFO">
        <appender-ref ref="file"/>
    </root>

    <!-- Uncomment this if you want to only change Flink's logging -->
    <!--<logger name="org.apache.flink" level="INFO">-->
        <!--<appender-ref ref="file"/>-->
    <!--</logger>-->

    <!-- The following lines keep the log level of common libraries/connectors on
         log level INFO. The root logger does not override this. You have to manually
         change the log levels here. -->
    <logger name="akka" level="INFO">
        <appender-ref ref="file"/>
    </logger>
    <logger name="org.apache.kafka" level="INFO">
        <appender-ref ref="file"/>
    </logger>
    <logger name="org.apache.hadoop" level="INFO">
        <appender-ref ref="file"/>
    </logger>
    <logger name="org.apache.zookeeper" level="INFO">
        <appender-ref ref="file"/>
    </logger>

    <!-- Suppress the irrelevant (wrong) warnings from the Netty channel handler -->
    <logger name="org.apache.flink.shaded.akka.org.jboss.netty.channel.DefaultChannelPipeline" level="ERROR">
        <appender-ref ref="file"/>
    </logger>
</configuration>