title: spring-boot application get warning: CONSOLE_LOG_PATTERN_IS_UNDEFINED
body: <p>There is a <strong>spring-boot</strong> <em>(2.0.0.RELEASE)</em> application as part of the <strong>spring-cloud</strong> <em>(Finchley.M9)</em> cluster.<br />
  On startup, it always print following line:</p>
  <blockquote>
  <p>CONSOLE_LOG_PATTERN_IS_UNDEFINEDCONSOLE_LOG_PATTERN_IS_UNDEFINEDCONSOLE_LOG_PATTERN_IS_UNDEFINED</p>
  </blockquote>
  <hr />
  <p><em>(following are the configuration)</em></p>
  <p><strong>application.yml:</strong></p>
  <pre><code>## spring-boot configuration,
  
  # logging
  logging:
    file: &quot;log/hello.log&quot;
    pattern:
      console: &quot;[%d{yyyy-MM-dd HH:mm:ss.SSS}] %-5level [%t] [%logger - %line]: %m%n&quot;
      file: &quot;[%d{yyyy-MM-dd HH:mm:ss.SSS}] %-5level [%t] [%logger - %line]: %m%n&quot;
    level:
      root: INFO
  
  spring:
    application:
      name: eric-sc-hello
  
  server:
    port: 9191
  
  management:
    endpoints:
      web:
        exposure:
      include: &quot;*&quot;
  
  eureka:
    client:
      serviceUrl:
        defaultZone: http://localhost:8761/eureka/
  
  eric-sc-hello:
    ribbon:
      eureka:
        enabled: false
      listOfServers: localhost:9191,localhost:9192,localhost:9193
      ServerListRefreshInterval: 15000
  </code></pre>
  <p><strong>logback-spring.xml:</strong></p>
  <pre><code>&lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;
  &lt;configuration&gt;
    &lt;appender name=&quot;CONSOLE&quot; class=&quot;ch.qos.logback.core.ConsoleAppender&quot;&gt;
      &lt;encoder&gt;
        &lt;charset&gt;UTF-8&lt;/charset&gt;
        &lt;Pattern&gt;${CONSOLE_LOG_PATTERN}&lt;/Pattern&gt;
      &lt;/encoder&gt;
    &lt;/appender&gt;
    &lt;appender name=&quot;FILE&quot;
      class=&quot;ch.qos.logback.core.rolling.RollingFileAppender&quot;&gt;
      &lt;encoder&gt;
        &lt;pattern&gt;${FILE_LOG_PATTERN}&lt;/pattern&gt;
      &lt;/encoder&gt;
      &lt;file&gt;${LOG_FILE}&lt;/file&gt;
      &lt;rollingPolicy
        class=&quot;ch.qos.logback.core.rolling.FixedWindowRollingPolicy&quot;&gt;
        &lt;fileNamePattern&gt;${LOG_FILE}.%i&lt;/fileNamePattern&gt;
        &lt;minIndex&gt;1&lt;/minIndex&gt;
        &lt;maxIndex&gt;10&lt;/maxIndex&gt;
      &lt;/rollingPolicy&gt;
      &lt;triggeringPolicy
        class=&quot;ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy&quot;&gt;
        &lt;MaxFileSize&gt;10MB&lt;/MaxFileSize&gt;
      &lt;/triggeringPolicy&gt;
    &lt;/appender&gt;
  
    &lt;root level=&quot;INFO&quot;&gt;
      &lt;appender-ref ref=&quot;CONSOLE&quot; /&gt;
      &lt;appender-ref ref=&quot;FILE&quot; /&gt;
    &lt;/root&gt;
  &lt;/configuration&gt;
  </code></pre>
  <hr />
  <p>The warning says <code>CONSOLE_LOG_PATTERN</code> is undefined for 3 times.</p>
  <p>But <code>logging.pattern.console</code> is defined in <code>application.yml</code>, and the log lines in console is printed in the specified format.</p>
  <p>So, why the warning pop-up, and how can I remove it?</p>
  <hr />
  <h2>@Update</h2>
  <p>I already found some solutions, and had added an answer here: <a href="https://stackoverflow.com/a/62846599/">https://stackoverflow.com/a/62846599/</a></p>