spring-petclinic/src/main/resources/logback.xml

<?xml version="1.0" encoding="UTF-8"?>
<configuration scan="true" scanPeriod="30 seconds">

    <contextListener class="ch.qos.logback.classic.jul.LevelChangePropagator">
        <resetJUL>true</resetJUL>
    </contextListener>

    <!-- To enable JMX Management -->
    <jmxConfigurator/>

    <appender name="console" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>%-5level %logger{0} - %msg%n</pattern>
        </encoder>
    </appender>

    <logger name="org.springframework.samples.petclinic" level="debug"/>
    
     <logger name="org.springframework.web.servlet.view" level="debug"/>

    <root level="info">
        <appender-ref ref="console"/>
    </root>
</configuration>