Log4j2.xml with springboot is not generating log file

By default spring boot contains an integration with logback logging library. So you'll have to exclude the "default" and add a special starter that will handle the integration:

In the pom.xml make sure you have the following:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter</artifactId>
    <exclusions>
        <exclusion>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-logging</artifactId>
        </exclusion>
    </exclusions>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-log4j2</artifactId>
</dependency>

Optional: If you want to use an asynchronous logging, add also the following dependency:

<dependency>
    <groupId>com.lmax</groupId>
    <artifactId>disruptor</artifactId>
    <version>3.3.6</version> <!-- check the actual version it might be different -->
</dependency>

After this step you can start configuring the log4j2. There are plenty of sample configurations and tutorials about this, examples: here and here.

I won't dive into possible configurations of log4j2, but from the spring boot's standpoint I'll mention that you should place the log4j2's configurations into src/main/resources/log4j2.xml

You can try with the below log4j2.xml. This is working for me.

<?xml version="1.0" encoding="UTF-8"?>
<Configuration xmlns="http://logging.apache.org/log4j/2.0/config">
    <Properties>
        <Property name="basePath">/home/user/myapp/logs</Property>
    </Properties>
    <Appenders>
        <!-- File Appender -->
        <File name="FILE" fileName="${basePath}/my-app.log" append="true">
            <PatternLayout pattern="%-5p | %d{yyyy-MM-dd HH:mm:ss} | [%t] %C{2} (%F:%L) - %m%n" />
        </File>
        <!-- Console Appender -->
        <Console name="STDOUT" target="SYSTEM_OUT">
            <PatternLayout pattern="%-5p | %d{yyyy-MM-dd HH:mm:ss} | [%t] %C{2} (%F:%L) - %m%n" />
        </Console>
    </Appenders>
    <Loggers>
        <Logger name="com.abc.xyz" level="debug" />
        <Root level="info">
            <AppenderRef ref="STDOUT" />
            <AppenderRef ref="FILE" />
        </Root>
    </Loggers>
</Configuration>

1. Change the log file name and path accordingly.
2. Also change the package for the logger. <Logger name="com.abc.xyz" level="debug" />