Java – Spring Boot with log4j2 and tomcat

I’m having some trouble using the Spring Boot web application. I didn’t use embedded tomcat, I disabled it. My web application uses Log4j2 as the logger. No problem debugging in Eclipse and creating my log file, but not with external tomcat.
Here is my pom file:

<project xmlns="http://maven.apache.org/POM/4.0.0"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.14.RELEASE</version>
    <relativePath /> <!-- lookup parent from repository -->
  </parent>

<groupId>pos.com.incidents</groupId>
  <artifactId>pos-com-incidents</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>war</packaging>
  <name>pos-com-incidents</name>

<properties>
    <java.version>1.8</java.version>
  </properties>

<dependencies>

<!-- Spring -->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</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-test</artifactId>
      <scope>test</scope>
    </dependency>

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

<dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-tomcat</artifactId>
      <scope>provided</scope>
    </dependency>

<!-- Lombok -->
    <dependency>
      <groupId>org.projectlombok</groupId>
      <artifactId>lombok</artifactId>
      <optional>true</optional>
    </dependency>

<!-- Informix -->
    <dependency>
      <groupId>JDBCDrivers.Informix</groupId>
      <artifactId>ifxjdbc</artifactId>
      <version>4.10.JC4</version>
    </dependency>

<!-- Log4j -->
    <dependency>
      <groupId>org.apache.logging.log4j</groupId>
      <artifactId>log4j-api</artifactId>
    </dependency>

<!-- Jackson -->
    <dependency>
      <groupId>com.fasterxml.jackson.dataformat</groupId>
      <artifactId>jackson-dataformat-yaml</artifactId>
    </dependency>

<dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-databind</artifactId>
    </dependency>

<!-- Apache Commons -->
    <dependency>
      <groupId>org.apache.commons</groupId>
      <artifactId>commons-lang3</artifactId>
    </dependency>

<dependency>
      <groupId>org.apache.commons</groupId>
      <artifactId>commons-collections4</artifactId>
      <version>4.0</version>
    </dependency>

<dependency>
      <groupId>commons-io</groupId>
      <artifactId>commons-io</artifactId>
      <version>2.6</version>
    </dependency>

<dependency>
      <groupId>commons-beanutils</groupId>
      <artifactId>commons-beanutils</artifactId>
      <version>1.9.2</version>
    </dependency>

<dependency>
      <groupId>commons-validator</groupId>
      <artifactId>commons-validator</artifactId>
      <version>1.6</version>
    </dependency>

<!-- Joda -->
    <dependency>
      <groupId>joda-time</groupId>
      <artifactId>joda-time</artifactId>
    </dependency>
  </dependencies>

<build>
    <finalName>${artifactId}</finalName>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>

</project>

My Log4j2 configuration file. I love yml files.

Configuration:
  status: warn

appenders:
    Console:
      name: AppConsole
      target: SYSTEM_OUT
      PatternLayout:
        Pattern: "%style{%d{ISO8601}}{black} %highlight{%-5level }[%style{%t}{bright,blue}] %style{%C{1.}} {bright,yellow}: %msg%n%throwable"

RollingFile:
      - name: AppDetail
        fileName: ${catalina.home}/logs/Incidents.log
        filePattern: "${catalina.home}/logs/Incidents-%d{-yyyy-MM-dd-}-%i.log.gz"
        PatternLayout:
          pattern: "%d %p %C{1.} [%t] %m%n"
        Policies:
          OnStartupTriggeringPolicy: {}
          SizeBasedTriggeringPolicy:
            size: 50 MB
        DefaultRollOverStrategy:
          max: 30

Loggers:
    logger:
      - name: pos.sams.incidents.logging
        level: info
        additivity: false
        AppenderRef:
          - ref: AppDetail
          - ref: AppConsole

Root:
      level: info
      AppenderRef:
        ref: AppConsole

I don’t want to use Log4j2 as a logger for tomcat, but just for my application. What are the possible problems and solutions?

If anyone runs into this issue, please change ${catalina.home} to ${sys:catalina.home}, the documentation will help.

http://logging.apache.org/log4j/2.x/manual/configuration.html#PropertySubstitution