详细错误信息：
com.mongodb.MongoSocketOpenException: Exception opening socket
at com.mongodb.connection.SocketStream.open(SocketStream.java:63) ~[mongodb-driver-core-3.4.2.jar:na]
at com.mongodb.connection.InternalStreamConnection.open(InternalStreamConnection.java:115) ~[mongodb-driver-core-3.4.2.jar:na]
at com.mongodb.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:113) ~[mongodb-driver-core-3.4.2.jar:na]
at java.lang.Thread.run(Thread.java:748) [na:1.8.0_131]
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method) ~[na:1.8.0_131]
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:85) ~[na:1.8.0_131]
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) ~[na:1.8.0_131]
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) ~[na:1.8.0_131]
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) ~[na:1.8.0_131]
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172) ~[na:1.8.0_131]
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.8.0_131]
at java.net.Socket.connect(Socket.java:589) ~[na:1.8.0_131]
at com.mongodb.connection.SocketStreamHelper.initialize(SocketStreamHelper.java:57) ~[mongodb-driver-core-3.4.2.jar:na]
at com.mongodb.connection.SocketStream.open(SocketStream.java:58) ~[mongodb-driver-core-3.4.2.jar:na]
... 3 common frames omitted
在spring boot项目中没有配置 mongodb的信息，启动一直报异常，如果使用 ：
@SpringBootApplication(exclude = MongoAutoConfiguration.class)注解取消spring boot的自动配置，项目就启动不了。
求各位大神帮忙解答下，感激不尽。
问题已解决，只要在配置文件里把初始的 mongodb 取消掉就好了。