Splitting log files by time + size in logback

With logback, the file rolls over when the day passes or the size goes over 100MB.

Add the appender below to logback.xml

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<appender name="debug" class="ch.qos.logback.core.rolling.RollingFileAppender">   
    <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
      <level>DEBUG</level>
    </filter>
    <prudent>false</prudent>
    <file>/logs/debug.log</file>
    <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
        <fileNamePattern>/logs/old/debug.%d{yyyy-MM-dd}.%i.log</fileNamePattern>
        <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
          <maxFileSize>100mb</maxFileSize>
        </timeBasedFileNamingAndTriggeringPolicy>
        <maxHistory>30</maxHistory> 
    </rollingPolicy>
    <encoder>
        <pattern>[%-5level] %d{HH:mm:ss.SSS} %logger{36} - %msg%n</pattern>
    </encoder>
</appender>

<maxFileSize /> is the rollover size (kb and gb work too)
<maxHistory /> deletes logs older than 30 days, oldest first.