[RDS,mySQL] RDS 포트 변경 이슈com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

💡 RDS 포트를 보안 관련 이슈로 변경하였지만, yml에 변경된 포트를 반영해주지 않았기 때문에 발생한 이슈

에러 코드

2023-05-30 06:27:29.225 ERROR 58789 --- [nio-8021-exec-1] com.zaxxer.hikari.pool.HikariPool        : HikariPool-1 - Exception during pool initialization.

com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
	at com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:174) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:64) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:824) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:444) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:237) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:198) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:138) ~[HikariCP-4.0.3.jar:na]
	at com.zaxxer.hikari.pool.PoolBase.newConnection(PoolBase.java:364) ~[HikariCP-4.0.3.jar:na]
	at com.zaxxer.hikari.pool.PoolBase.newPoolEntry(PoolBase.java:206) ~[HikariCP-4.0.3.jar:na]
	at com.zaxxer.hikari.pool.HikariPool.createPoolEntry(HikariPool.java:476) ~[HikariCP-4.0.3.jar:na]
	at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:561) ~[HikariCP-4.0.3.jar:na]
	at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:115) ~[HikariCP-4.0.3.jar:na]
	at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:112) ~[HikariCP-4.0.3.jar:na]
	at org.springframework.jdbc.datasource.DataSourceUtils.fetchConnection(DataSourceUtils.java:159) ~[spring-jdbc-5.3.26.jar:5.3.26]
	at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:117) ~[spring-jdbc-5.3.26.jar:5.3.26]
	at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:80) ~[spring-jdbc-5.3.26.jar:5.3.26]
	at org.mybatis.spring.transaction.SpringManagedTransaction.openConnection(SpringManagedTransaction.java:80) ~[mybatis-spring-2.0.7.jar:2.0.7]
	at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:67) ~[mybatis-spring-2.0.7.jar:2.0.7]
	at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:337) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:86) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:62) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:325) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:89) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:151) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:145) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:140) ~[mybatis-3.5.9.jar:3.5.9]
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77) ~[na:na]
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
	at java.base/java.lang.reflect.Method.invoke(Method.java:568) ~[na:na]
	at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:427) ~[mybatis-spring-2.0.7.jar:2.0.7]
	at jdk.proxy2/jdk.proxy2.$Proxy62.selectList(Unknown Source) ~[na:na]
	at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:224) ~[mybatis-spring-2.0.7.jar:2.0.7]
	at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:147) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:80) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.binding.MapperProxy$PlainMethodInvoker.invoke(MapperProxy.java:145) ~[mybatis-3.5.9.jar:3.5.9]
	at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:86) ~[mybatis-3.5.9.jar:3.5.9]
	at jdk.proxy3/jdk.proxy3.$Proxy63.selectALLPlaceWithFilterAndKeyword(Unknown Source) ~[na:na]
	at com.bside.cuokkamap.service.PlaceServiceImpl.selectALLPlaceWithFilterAndKeyword(PlaceServiceImpl.java:34) ~[main/:na]
	at com.bside.cuokkamap.controller.PlaceController.getALLPlaceWithFilterAndKeyword(PlaceController.java:107) ~[main/:na]
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77) ~[na:na]
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
	at java.base/java.lang.reflect.Method.invoke(Method.java:568) ~[na:na]
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-5.3.26.jar:5.3.26]
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150) ~[spring-web-5.3.26.jar:5.3.26]
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) ~[spring-webmvc-5.3.26.jar:5.3.26]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.3.26.jar:5.3.26]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808) ~[spring-webmvc-5.3.26.jar:5.3.26]
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.3.26.jar:5.3.26]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1072) ~[spring-webmvc-5.3.26.jar:5.3.26]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:965) ~[spring-webmvc-5.3.26.jar:5.3.26]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.26.jar:5.3.26]
	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909) ~[spring-webmvc-5.3.26.jar:5.3.26]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:528) ~[tomcat-embed-core-9.0.73.jar:4.0.FR]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.26.jar:5.3.26]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:596) ~[tomcat-embed-core-9.0.73.jar:4.0.FR]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:209) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.73.jar:9.0.73]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.3.26.jar:5.3.26]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.26.jar:5.3.26]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.3.26.jar:5.3.26]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.26.jar:5.3.26]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.3.26.jar:5.3.26]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.26.jar:5.3.26]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:167) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:492) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:130) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:389) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:926) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1791) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-9.0.73.jar:9.0.73]
	at java.base/java.lang.Thread.run(Thread.java:833) ~[na:na]
Caused by: com.mysql.cj.exceptions.CJCommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:na]
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:77) ~[na:na]
	at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:na]
	at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499) ~[na:na]
	at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480) ~[na:na]
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:105) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:151) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.exceptions.ExceptionFactory.createCommunicationsException(ExceptionFactory.java:167) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:89) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.NativeSession.connect(NativeSession.java:120) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:944) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:814) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	... 89 common frames omitted
Caused by: java.net.SocketTimeoutException: Connect timed out
	at java.base/sun.nio.ch.NioSocketImpl.timedFinishConnect(NioSocketImpl.java:546) ~[na:na]
	at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:597) ~[na:na]
	at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:327) ~[na:na]
	at java.base/java.net.Socket.connect(Socket.java:633) ~[na:na]
	at com.mysql.cj.protocol.StandardSocketFactory.connect(StandardSocketFactory.java:153) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:63) ~[mysql-connector-j-8.0.32.jar:8.0.32]
	... 92 common frames omitted

org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
### The error may exist in mapper/placeMapper.xml
### The error may involve com.bside.cuokkamap.dao.PlaceDAO.selectALLPlaceWithFilterAndKeyword
### The error occurred while executing a query
### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.

핵심 요점

• yml 파일에서 DB 연결 설정 시 포트번호를 명시해야 함
  • 기본 포트(3306) 사용시 따로 추가해주지 않아도 되나, 한번 RDS가 털려본 이후 포트는 다른 것으로 변경하는 것을 추천받아 변경함

해결 방안

1. yml 파일에 DB 정보 입력시 포트번호 추가

spring:
  datasource: # dataSource DB 연결
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://[RDS 엔드포인트]:[⭐️포트번호⭐️]
    username: [암호화 후 입력하기_DB 유저명] 
    password: [암호화 후 입력하기_DB 비밀번호]