Using Logback to catalina.out-CodePudding

I am using Logback in an application running in Tomcat. While my application works and, in the debugger, I see my logging statements reached, these statements never reach /opt/tomcat/logs/catalina.out. (By the way, I do see these statements in the IntelliJ IDEA debugger console, but upon deployment, they don't reach catalina.out.) Where do I begin?

In my WAR, WEB-INF/classes/logback.xml looks like this:

<configuration>
  <appender name="FILE" >
    <file>${catalina.base}/logs/catalina.out</file>
    <rollingPolicy >
      <maxFileSize>10MB</maxFileSize>
      <maxHistory>10</maxHistory>
    </rollingPolicy>
    <immediateFlush>true</immediateFlush>
    <encoder >
      <pattern>