用compass community和java程序连不上远程linux上的mongodb问题解决

1.用compass community连接时：

2.用java程序连接时：

com.mongodb.MongoSocketOpenException: Exception opening socket
	at com.mongodb.connection.SocketStream.open(SocketStream.java:62) ~[mongodb-driver-core-3.5.0.jar:na]
	at com.mongodb.connection.InternalStreamConnection.open(InternalStreamConnection.java:107) ~[mongodb-driver-core-3.5.0.jar:na]
	at com.mongodb.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:111) ~[mongodb-driver-core-3.5.0.jar:na]
	at java.lang.Thread.run(Unknown Source) [na:1.8.0_171]
Caused by: java.net.SocketTimeoutException: connect timed out
	at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method) ~[na:1.8.0_171]
	at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source) ~[na:1.8.0_171]
	at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source) ~[na:1.8.0_171]
	at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source) ~[na:1.8.0_171]
	at java.net.AbstractPlainSocketImpl.connect(Unknown Source) ~[na:1.8.0_171]
	at java.net.PlainSocketImpl.connect(Unknown Source) ~[na:1.8.0_171]
	at java.net.SocksSocketImpl.connect(Unknown Source) ~[na:1.8.0_171]
	at java.net.Socket.connect(Unknown Source) ~[na:1.8.0_171]
	at com.mongodb.connection.SocketStreamHelper.initialize(SocketStreamHelper.java:59) ~[mongodb-driver-core-3.5.0.jar:na]
	at com.mongodb.connection.SocketStream.open(SocketStream.java:57) ~[mongodb-driver-core-3.5.0.jar:na]
	... 3 common frames omitted

原因：linux上的防火墙没有关。
我是centos7，关闭防火墙：
systemctl stop firewalld.service
systemctl disable firewalld.service
开始防火墙：
systemctl start firewalld.service
systemctl enable firewalld.service
查看防火墙状态：
systemctl status firewalld
关闭之后可以正常连接。