When deploying the project on the server, starting tomcat fails. When viewing the error log, the main display is as follows:
org.springframework.jmx.export.UnableToRegisterMBeanException: Unable to register MBean [HikariDataSource (HikariPool-2)] with key 'dataSource'; nested exception is javax.management.InstanceAlreadyExistsException: com.zaxxer.hikari:name=dataSource,type=HikariDataSource
After querying, we learned that there may be multiple project instances under webapps in the tomcat installation directory. If you only need one, delete the others.
Finally, restart the project.