​
Use a config file

To further customize your logging at an individual logger-level, you can use a custom log4j configuration file. First, bind your custom log4j configuration file to the /app/resources/log4j2.xml path in the container. Here’s the default configuration file: 
<?xml version="1.0" encoding="UTF-8"?>
<configuration status="warn">

    <Properties>
        <Property name="LOG4J2_TIME_FORMAT">yyyy-MM-dd'T'HH:mm:ss.SSSZ</Property>
        <Property name="LOG4J2_APPENDER_LAYOUT">pattern</Property>
        <Property name="LOG4J2_ROOT_LEVEL">info</Property>
        <Property name="LOG4J2_ORG_APACHE_KAFKA_LEVEL">warn</Property>
        <Property name="LOG4J2_IO_KCACHE_LEVEL">warn</Property>
        <Property name="LOG4J2_IO_VERTX_LEVEL">warn</Property>
        <Property name="LOG4J2_IO_NETTY_LEVEL">error</Property>
        <Property name="LOG4J2_IO_CONDUKTOR_LEVEL">info</Property>
        <Property name="LOG4J2_IO_CONDUKTOR_PROXY_AUTHORIZATION_LEVEL">info</Property>
        <Property name="LOG4J2_IO_CONDUKTOR_PROXY_REBUILDER_COMPONENTS_LEVEL">info</Property>
        <Property name="LOG4J2_IO_CONDUKTOR_PROXY_SERVICE_LEVEL">info</Property>
        <Property name="LOG4J2_IO_CONDUKTOR_PROXY_NETWORK_LEVEL">info</Property>
        <Property name="LOG4J2_IO_CONDUKTOR_UPSTREAM_THREAD_LEVEL">warn</Property>
        <Property name="LOG4J2_IO_MICROMETER_LEVEL">error</Property>
        <Property name="LOG4J2_IO_CONFLUENT_LEVEL">warn</Property>
    </Properties>

    <appenders>
        <Console name="json" target="SYSTEM_OUT">
            <JsonLayout complete="false" compact="true" eventEol="true" properties="true"
                        objectMessageAsJsonObject="true">
                <KeyValuePair key="timestamp" value="$${date:${env:LOG4J2_TIME_FORMAT}}"/>
            </JsonLayout>
        </Console>
        <Console name="pattern" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{${env:LOG4J2_TIME_FORMAT}} [%red{%10.25t}] [%green{%-5p}] [%blue{%c{1}:%L}] - %m%n"/>
        </Console>
    </appenders>

    <loggers>
        <logger name="org.apache.kafka" level="${env:LOG4J2_ORG_APACHE_KAFKA_LEVEL}" additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.kcache" level="${env:LOG4J2_IO_KCACHE_LEVEL}" additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.vertx" level="${env:LOG4J2_IO_VERTX_LEVEL}" additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.netty" level="${env:LOG4J2_IO_NETTY_LEVEL}" additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.conduktor" level="${env:LOG4J2_IO_CONDUKTOR_LEVEL}" additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.conduktor.proxy.authorization" level="${env:LOG4J2_IO_CONDUKTOR_PROXY_AUTHORIZATION_LEVEL}"
                additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.conduktor.proxy.rebuilder.components"
                level="${env:LOG4J2_IO_CONDUKTOR_PROXY_REBUILDER_COMPONENTS_LEVEL}" additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.conduktor.proxy.service" level="${env:LOG4J2_IO_CONDUKTOR_PROXY_SERVICE_LEVEL}"
                additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.conduktor.proxy.thread.UpstreamThread" level="${env:LOG4J2_IO_CONDUKTOR_UPSTREAM_THREAD_LEVEL}"
                additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.conduktor.proxy.network" level="${env:LOG4J2_IO_CONDUKTOR_PROXY_NETWORK_LEVEL}"
                additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.micrometer" level="${env:LOG4J2_IO_MICROMETER_LEVEL}" additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="org.hibernate.validator.internal.util" level="ERROR" additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>
        <logger name="io.confluent" level="${env:LOG4J2_IO_CONFLUENT_LEVEL}" additivity="false">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </logger>

        <AsyncRoot level="${env:LOG4J2_ROOT_LEVEL}">
            <appender-ref ref="${env:LOG4J2_APPENDER_LAYOUT}"/>
        </AsyncRoot>
    </loggers>
</configuration>