在ext项目中 在docroot/WEB-INF/ext-impl/src 目录下 创建文件夹 META-INF 把源码对应目录中的 log4j.dtd复制至此。

把源码中对应目录的portal-log4j.xml复制到此目录下 更名为 portal-log4j-ext.xml 内容修改为

<?xml version="1.0"?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">

<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
	<appender name="CONSOLE" class="org.apache.log4j.ConsoleAppender">
		<layout class="org.apache.log4j.EnhancedPatternLayout">
			<param name="ConversionPattern" value="%d{yyyy MM dd HH:mm:ss,SSS} %-5p [%t][%c{1}] %m%n" />
		</layout>
	</appender>

	<appender name="FILE" class="org.apache.log4j.rolling.RollingFileAppender">
		<rollingPolicy class="org.apache.log4j.rolling.TimeBasedRollingPolicy">
			<param name="FileNamePattern" value="@liferay.home@/logs/liferay@spi.id@.%d{yyyy-MM-dd}.log" />
		</rollingPolicy>

		<layout class="org.apache.log4j.EnhancedPatternLayout">
			<param name="ConversionPattern" value="%d{yyyy MM dd HH:mm:ss,SSS} %-5p [%t][%c{1}] %m%n" />
		</layout>
	</appender>
	<appender name="ASYNC" class="org.apache.log4j.AsyncAppender">
        <appender-ref ref="CONSOLE" />
        <appender-ref ref="FILE" />
	</appender>
        <category name="com.liferay.portlet.login.util.LoginLog">
		<priority value="INFO" />
	</category>
	<category name="com.liferay.portlet.login.util.LogoutLog">
		<priority value="INFO" />
	</category>
	<category name="com.liferay.portal.kernel.search.Hits">
		<priority value="INFO" />
	</category>
	<category name="com.liferay.portlet.blogs.action.BlogFilterService">
		<priority value="INFO" />
	</category>
	<root>
		<priority value="INFO" />
		<appender-ref ref="ASYNC" />
	</root>
</log4j:configuration>