当两个 logback.xml 在 Websphere 服务器上运行时，日志被合并

Question

The problem I'm facing is, I have an application which uses a jar file(jar1) containing the logback.xml(having destination folder for its log files) and another application also using a jar file(jar2) containing another logback.xml(having different destination folder for its log files). For the first application I'm using a classloader with a share file configuration of jar1. Now in this case, the logs are getting merged. Some logs are getting created in the first destination folder for the second application and vice-versa. I'm using WebSphere9. Is there a way, the log files get created in their specific destination folder, without the logs getting merged?

Keeping the first classloader, I have tried using a second classloader with a share file configuration of jar2,for second application. But in this case either of the application works. So this solution was ruled out.

The logback.xml of first application:

<?xml version="1.0" encoding="UTF-8"?>

<appender name="consoleAppender"
    class="ch.qos.logback.core.ConsoleAppender">
    <layout class="ch.qos.logback.classic.PatternLayout">
        <Pattern>%-50(%level %logger{35}) cn=%contextName - %msg%n</Pattern>
    </layout>
</appender>

<appender name="mainAppender"
    class="ch.qos.logback.core.rolling.RollingFileAppender">
    <file>${USR_HOME}/yoda.log</file>
    <rollingPolicy
        class="ch.qos.logback.core.rolling.FixedWindowRollingPolicy">
        <fileNamePattern>${USR_HOME}/yoda.%i.log</fileNamePattern>
        <minIndex>1</minIndex>
        <maxIndex>20</maxIndex>
        <cleanHistoryOnStart>true</cleanHistoryOnStart>
    </rollingPolicy>
    <triggeringPolicy
        class="ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy">
        <maxFileSize>50MB</maxFileSize>
    </triggeringPolicy>
    <encoder
        class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
        <Pattern%-50(%level %logger{35}) cn=%contextName - %msg%n</Pattern>
    </encoder>
    <prudent>false</prudent>
</appender>

<root name="MAIN_LOGGER" level="ERROR" additivity="true">
    <appender-ref ref="mainAppender" />
</root>

The logback.xml for second application:

 <?xml version="1.0" encoding="UTF-8"?>

<appender name="consoleAppender"
    class="ch.qos.logback.core.ConsoleAppender">
    <layout class="ch.qos.logback.classic.PatternLayout">
        <Pattern>%-50(%level %logger{35}) cn=%contextName - %msg%n</Pattern>
    </layout>
</appender>

<appender name="mainAppender"
    class="ch.qos.logback.core.rolling.RollingFileAppender">
    <file>${AG_HOME}/kenobi.log</file>
    <rollingPolicy
        class="ch.qos.logback.core.rolling.FixedWindowRollingPolicy">
        <fileNamePattern>${AG_HOME}/kenobi.%i.log</fileNamePattern>
        <minIndex>1</minIndex>
        <maxIndex>20</maxIndex>
        <cleanHistoryOnStart>true</cleanHistoryOnStart>
    </rollingPolicy>
    <triggeringPolicy
        class="ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy">
        <maxFileSize>50MB</maxFileSize>
    </triggeringPolicy>
    <encoder
        class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
        <Pattern%-50(%level %logger{35}) cn=%contextName - %msg%n</Pattern>
    </encoder>
    <prudent>false</prudent>
</appender>

<root name="MAIN_LOGGER" level="ERROR" additivity="true">
    <appender-ref ref="mainAppender" />
</root>

Answer 1

It looks like only one of the logback config file gets picked up by the classloader shared by both applications. Instead of packaging the logback or log4j config file in your application jar files, try to add the two config files in two shared libraries defined on WebSphere, and config your application to reference your shared libraries.

Take a look at IBM Knowledge Center's article on reference shared libraries. https://www.ibm.com/support/knowledgecenter/SS7K4U_9.0.5/com.ibm.websphere.zseries.doc/ae/tcws_sharedlib_app.html

Answer 2

In both the logback.xml files, you have defined root level logger only. Root level logger logs from all the applications in logger file.

Try, defining seperate logger in logback

<logger name="com.x.y.z" level="INFO" additivity="false">
    <appender-ref ref="refToAppender" />        
</logger>