一、按天记录日志，日志保留7天
<RollingFile name="rollingFile" fileName="log/main.log" filePattern="log/$${date:yyyy-MM}/main-%d{yyyy-MM-dd}.log.gz"> <PatternLayout pattern="[%d{yyyy-MM-dd HH:mm:ss}] [%-5p] %l - %m%n"/> <Policies> <TimeBasedTriggeringPolicy modulate="true" interval="1"/> </Policies> <DefaultRolloverStrategy> <Delete basePath="log" maxDepth="2"> <IfFileName glob="*/*.log.gz" /> <IfLastModified age="7d" /> </Delete> </DefaultRolloverStrategy> </RollingFile>二、按小时记录日志，日志保留6天
<RollingFile name="rollingFile" fileName="log/main.log" filePattern="log/$${date:yyyy-MM}/main-%d{yyyy-MM-dd-HH}.log.gz"> <PatternLayout pattern="[%d{yyyy-MM-dd HH:mm:ss}] [%-5p] %l - %m%n"/> <Policies> <TimeBasedTriggeringPolicy modulate="true" interval="1"/> </Policies> <DefaultRolloverStrategy> <Delete basePath="log" maxDepth="2"> <IfFileName glob="*/*.log.gz" /> <IfLastModified age="6d" /> </Delete> </DefaultRolloverStrategy> </RollingFile>三、按大小记录日志，满20MB记录一个日志，日志保留7天；同一天最多生成10个20MB日志文件，由filePattern中的%i和DefaultRolloverStrategy中max的值决定
<RollingFile name="rollingFile" fileName="log/main.log" filePattern="log/$${date:yyyy-MM}/main-%d{yyyy-MM-dd}-%i.log.gz"> <PatternLayout pattern="[%d{yyyy-MM-dd HH:mm:ss}] [%-5p] %l - %m%n"/> <Policies> <TimeBasedTriggeringPolicy /> <SizeBasedTriggeringPolicy size="20 MB" /> </Policies> <DefaultRolloverStrategy max="10"> <Delete basePath="log" maxDepth="2"> <IfFileName glob="*/*.log.gz" /> <IfLastModified age="7d" /> </Delete> </DefaultRolloverStrategy> </RollingFile>关键点在于 filePattern后的日期格式，以及TimeBasedTriggeringPolicy的interval；日期格式精确到哪一位，interval也精确到哪一个单位
<?xml version="1.0" encoding="UTF-8"?> <Configuration status="warn" nmonitorInterval="30"> <Appenders> <RollingFile name="rollingFile" fileName="log/main.log" filePattern="log/$${date:yyyy-MM}/main-%d{yyyy-MM-dd}.log.gz"> <PatternLayout pattern="[%d{yyyy-MM-dd HH:mm:ss}] [%-5p] %l - %m%n"/> <Policies> <TimeBasedTriggeringPolicy modulate="true" interval="1"/> </Policies> <DefaultRolloverStrategy> <Delete basePath="log" maxDepth="2"> <IfFileName glob="*/*.log.gz" /> <IfLastModified age="7d" /> </Delete> </DefaultRolloverStrategy> </RollingFile> </Appenders> <Loggers> <Root level="info"> <AppenderRef ref="rollingFile"/> </Root> </Loggers> </Configuration>官方参考文档：https://logging.apache.org/log4j/2.x/manual/appenders.html
