之前也部署过一个小demo，连接数据库的代码是一样的，那个小demo就可以没问题，现在这个就出现问题了，试了改动time_out 参数，改变mysql-conect的版本号，改变url的连接参数，都不行（我的linux上的数据库版本是8.0.23）。报错信息如下，请各位大佬指教！
16:09:50.481 [http-nio-7000-exec-1] INFO org.springframework.web.servlet.DispatcherServlet - Completed initialization in 2 ms
16:11:26.664 [Druid-ConnectionPool-Create-646910062] ERROR com.alibaba.druid.pool.DruidDataSource - create connection SQLException, url: jdbc:mysql://47.100.7.73:3306/blog?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=GMT, errorCode 0, state 08S01
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-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:64) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:833) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:453) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:246) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:198) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1652) ~[druid-1.2.2.jar!/:1.2.2]
at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1718) ~[druid-1.2.2.jar!/:1.2.2]
at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2785) [druid-1.2.2.jar!/:1.2.2]
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 sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_292]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[?:1.8.0_292]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:1.8.0_292]
at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[?:1.8.0_292]
at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:105) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:151) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.exceptions.ExceptionFactory.createCommunicationsException(ExceptionFactory.java:167) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:89) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.NativeSession.connect(NativeSession.java:144) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:953) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:823) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
... 6 more
Caused by: java.net.ConnectException: Connection timed out (Connection timed out)
at java.net.PlainSocketImpl.socketConnect(Native Method) ~[?:1.8.0_292]
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) ~[?:1.8.0_292]
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) ~[?:1.8.0_292]
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) ~[?:1.8.0_292]
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[?:1.8.0_292]
at java.net.Socket.connect(Socket.java:607) ~[?:1.8.0_292]
at com.mysql.cj.protocol.StandardSocketFactory.connect(StandardSocketFactory.java:155) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:63) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.NativeSession.connect(NativeSession.java:144) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:953) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:823) ~[mysql-connector-java-8.0.23.jar!/:8.0.23]
... 6 more
