springboot启动，logback会在/tmp目录下生成spring.log文件。如果已经存在spring.log文件，会因为权限读写失败。如下：

Caused by: java.lang.IllegalStateException: Logback configuration error detected: 
ERROR in ch.qos.logback.core.rolling.RollingFileAppender[FILE] - openFile(/tmp/spring.log,true) call failed. java.io.FileNotFoundException: /tmp/spring.log (Permission denied)
        at org.springframework.boot.logging.logback.LogbackLoggingSystem.loadConfiguration(LogbackLoggingSystem.java:169)
        at org.springframework.boot.logging.AbstractLoggingSystem.initializeWithSpecificConfig(AbstractLoggingSystem.java:67)
        at org.springframework.boot.logging.AbstractLoggingSystem.initialize(AbstractLoggingSystem.java:57)
        at org.springframework.boot.logging.logback.LogbackLoggingSystem.initialize(LogbackLoggingSystem.java:117)
        at org.springframework.boot.context.logging.LoggingApplicationListener.initializeSystem(LoggingApplicationListener.java:269)
        ... 22 more

是因为logback.xml引入了logback内置文件base.xml.

进入base.xml文件会发现springboot生成spring.log文件：

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

<!--
Base logback configuration provided for compatibility with Spring Boot 1.1
-->

<included>
	<include resource="org/springframework/boot/logging/logback/defaults.xml" />
	<property name="LOG_FILE" value="${LOG_FILE:-${LOG_PATH:-${LOG_TEMP:-${java.io.tmpdir:-/tmp}}}/spring.log}"/>
	<include resource="org/springframework/boot/logging/logback/console-appender.xml" />
	<include resource="org/springframework/boot/logging/logback/file-appender.xml" />
	<root level="INFO">
		<appender-ref ref="CONSOLE" />
		<appender-ref ref="FILE" />
	</root>
</included>

多用户相同项目部署会出现覆盖权限不足的问题，导致启动失败。

解决方法

在application.yml 重定义日志文件生成路径：
logging:
file: logs/xxx.log