Logging system failed to initialize using configuration from ‘classpath:log4j2.xml

 引用log4j2报错：Dependency ‘org.springframework.boot:spring-boot-starter-log4j2:’ not found

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

一开始是用上面引用，但是项目提示找不到依赖库。然后参考别人改成以下方式。添加成功之后，运行又报错。

   <!-- 2.17.0修复漏洞版本 -->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>2.17.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.17.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-slf4j-impl</artifactId>
            <version>2.17.0</version>
        </dependency>

报错信息：

在IDEA中，springboot的项目，引入log4j2日志配置时报错:
Logging system failed to initialize using configuration from ‘classpath:log4j2.xml’
java.lang.IllegalStateException: Logback configuration error detected: 

分析
配置log4j2.xml文件没有少。

 参考网上说明，主要是sprinpboot原来logback包存在导致冲突，检查包含lib里确实是有logback包。

参考网上的配置，更新pom.xml，更新完成之后，清除一下缓存，重新同步maven相关配置。即可解决问题。

pom.xml 整个源码配置如下

<?xml version="1.0" encoding="UTF-8"?>
<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.gtk</groupId>
    <artifactId>mbblibser</artifactId>
    <version>1.0-SNAPSHOT</version>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <version>2.5.6</version>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-logging</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.apache.logging.log4j</groupId>
                    <artifactId>log4j-core</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.apache.logging.log4j</groupId>
                    <artifactId>log4j-api</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.apache.logging.log4j</groupId>
                    <artifactId>log4j-slf4j-impl</artifactId>
                </exclusion>

            </exclusions>
        </dependency>

        <dependency>
            <groupId>com.google.collections</groupId>
            <artifactId>google-collections</artifactId>
            <version>1.0</version>
        </dependency>



        <!-- 2.17.0修复漏洞版本 -->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>2.17.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.17.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-slf4j-impl</artifactId>
            <version>2.17.0</version>
        </dependency>

    </dependencies>


</project>