Tomcat 서버를 사용하면 한 번씩 마주하게 될 에러이다.
Several ports (5050, 8081) required by Tomcat v9.0 Server at localhost are already in use. The server may already be running in another process, or a system process may be using the port. To start this server you will need to stop the other process or change the port number(s).
관리자 권한으로 cmd 실행
netstat -ano | findstr :[포트번호]
taskkill /PID [PID] /F