1.最近在使用spring-boot和用spring-data-mongo操作mongodb

2.每天早上查看服务器日志都发现报了同一个错，估计是在一整晚没人访问服务器，第二天一旦有人访问就会发生错误

3.错误日志为：

07:51:35.185 [cluster-ClusterId{value='59295e6c3532f223626a2ca0', description='null'}-localhost:27017] INFO  org.mongodb.driver.cluster - Exception in monitor thread while connecting to server localhost:27017 
com.mongodb.MongoSocketReadTimeoutException: Timeout while receiving message
    at com.mongodb.connection.InternalStreamConnection.translateReadException(InternalStreamConnection.java:477)
    at com.mongodb.connection.InternalStreamConnection.receiveMessage(InternalStreamConnection.java:228)
    at com.mongodb.connection.CommandHelper.receiveReply(CommandHelper.java:134)
    at com.mongodb.connection.CommandHelper.receiveCommandResult(CommandHelper.java:121)
    at com.mongodb.connection.CommandHelper.executeCommand(CommandHelper.java:32)
    at com.mongodb.connection.InternalStreamConnectionInitializer.initializeConnectionDescription(InternalStreamConnectionInitializer.java:85)
    at com.mongodb.connection.InternalStreamConnectionInitializer.initialize(InternalStreamConnectionInitializer.java:45)
    at com.mongodb.connection.InternalStreamConnection.open(InternalStreamConnection.java:116)
    at com.mongodb.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:127)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.SocketTimeoutException: Read timed out
    at java.net.SocketInputStream.socketRead0(Native Method)
    at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
    at java.net.SocketInputStream.read(SocketInputStream.java:171)
    at java.net.SocketInputStream.read(SocketInputStream.java:141)
    at com.mongodb.connection.SocketStream.read(SocketStream.java:85)
    at com.mongodb.connection.InternalStreamConnection.receiveResponseBuffers(InternalStreamConnection.java:494)
    at com.mongodb.connection.InternalStreamConnection.receiveMessage(InternalStreamConnection.java:224)
    ... 8 common frames omitted
07:51:31.683 [cluster-ClusterId{value='59295e583532f22362cf3b92', description='null'}-localhost:27017] INFO  org.mongodb.driver.cluster - Exception in monitor thread while connecting to server localhost:27017 
com.mongodb.MongoSocketReadTimeoutException: Timeout while receiving message
    at com.mongodb.connection.InternalStreamConnection.translateReadException(InternalStreamConnection.java:477)
    at com.mongodb.connection.InternalStreamConnection.receiveMessage(InternalStreamConnection.java:228)
    at com.mongodb.connection.CommandHelper.receiveReply(CommandHelper.java:134)
    at com.mongodb.connection.CommandHelper.receiveCommandResult(CommandHelper.java:121)
    at com.mongodb.connection.CommandHelper.executeCommand(CommandHelper.java:32)
    at com.mongodb.connection.InternalStreamConnectionInitializer.initializeConnectionDescription(InternalStreamConnectionInitializer.java:85)
    at com.mongodb.connection.InternalStreamConnectionInitializer.initialize(InternalStreamConnectionInitializer.java:45)
    at com.mongodb.connection.InternalStreamConnection.open(InternalStreamConnection.java:116)
    at com.mongodb.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:127)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.SocketTimeoutException: Read timed out
    at java.net.SocketInputStream.socketRead0(Native Method)
    at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
    at java.net.SocketInputStream.read(SocketInputStream.java:171)
    at java.net.SocketInputStream.read(SocketInputStream.java:141)
    at com.mongodb.connection.SocketStream.read(SocketStream.java:85)
    at com.mongodb.connection.InternalStreamConnection.receiveResponseBuffers(InternalStreamConnection.java:494)
    at com.mongodb.connection.InternalStreamConnection.receiveMessage(InternalStreamConnection.java:224)
    ... 8 common frames omitted
07:51:35.780 [cluster-ClusterId{value='59295e403532f2236234b535', description='null'}-localhost:27017] INFO  org.mongodb.driver.cluster - Exception in monitor thread while connecting to server localhost:27017 
com.mongodb.MongoSocketReadTimeoutException: Timeout while receiving message
    at com.mongodb.connection.InternalStreamConnection.translateReadException(InternalStreamConnection.java:477)
    at com.mongodb.connection.InternalStreamConnection.receiveMessage(InternalStreamConnection.java:228)
    at com.mongodb.connection.CommandHelper.receiveReply(CommandHelper.java:134)
    at com.mongodb.connection.CommandHelper.receiveCommandResult(CommandHelper.java:121)
    at com.mongodb.connection.CommandHelper.executeCommand(CommandHelper.java:32)
    at com.mongodb.connection.InternalStreamConnectionInitializer.initializeConnectionDescription(InternalStreamConnectionInitializer.java:85)
    at com.mongodb.connection.InternalStreamConnectionInitializer.initialize(InternalStreamConnectionInitializer.java:45)
    at com.mongodb.connection.InternalStreamConnection.open(InternalStreamConnection.java:116)
    at com.mongodb.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:127)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.SocketTimeoutException: Read timed out
    at java.net.SocketInputStream.socketRead0(Native Method)
    at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
    at java.net.SocketInputStream.read(SocketInputStream.java:171)
    at java.net.SocketInputStream.read(SocketInputStream.java:141)
    at com.mongodb.connection.SocketStream.read(SocketStream.java:85)
    at com.mongodb.connection.InternalStreamConnection.receiveResponseBuffers(InternalStreamConnection.java:494)
    at com.mongodb.connection.InternalStreamConnection.receiveMessage(InternalStreamConnection.java:224)
    ... 8 common frames omitted
08:01:39.239 [cluster-ClusterId{value='59295e583532f22362cf3b92', description='null'}-localhost:27017] INFO  org.mongodb.driver.connection - Opened connection [connectionId{localValue:9, serverValue:828}] to localhost:27017 
08:01:39.248 [cluster-ClusterId{value='59295e583532f22362cf3b92', description='null'}-localhost:27017] INFO  org.mongodb.driver.cluster - Monitor thread successfully connected to server with description ServerDescription{address=localhost:27017, type=STANDALONE, state=CONNECTED, ok=true, version=ServerVersion{versionList=[3, 4, 4]}, minWireVersion=0, maxWireVersion=5, maxDocumentSize=16777216, roundTripTimeNanos=340319} 
08:01:39.273 [cluster-ClusterId{value='59295e6c3532f223626a2ca0', description='null'}-localhost:27017] INFO  org.mongodb.driver.connection - Opened connection [connectionId{localValue:7, serverValue:827}] to localhost:27017 
08:01:39.274 [cluster-ClusterId{value='59295e403532f2236234b535', description='null'}-localhost:27017] INFO  org.mongodb.driver.connection - Opened connection [connectionId{localValue:7, serverValue:826}] to localhost:27017 
08:01:39.274 [cluster-ClusterId{value='59295e403532f2236234b535', description='null'}-localhost:27017] INFO  org.mongodb.driver.cluster - Monitor thread successfully connected to server with description ServerDescription{address=localhost:27017, type=STANDALONE, state=CONNECTED, ok=true, version=ServerVersion{versionList=[3, 4, 4]}, minWireVersion=0, maxWireVersion=5, maxDocumentSize=16777216, roundTripTimeNanos=105791} 
08:01:39.274 [cluster-ClusterId{value='59295e6c3532f223626a2ca0', description='null'}-localhost:27017] INFO  org.mongodb.driver.cluster - Monitor thread successfully connected to server with description ServerDescription{address=localhost:27017, type=STANDALONE, state=CONNECTED, ok=true, version=ServerVersion{versionList=[3, 4, 4]}, minWireVersion=0, maxWireVersion=5, maxDocumentSize=16777216, roundTripTimeNanos=532381}

4.尝试过一些解决方法，把链接mongodb的代码改成：

new MongoClient(new ServerAddress(env.getProperty("mongo.host"), Integer.valueOf(env.getProperty("mongo.port"))), Arrays.asList(credential), MongoClientOptions.builder()
                .socketTimeout(10000)
                .minHeartbeatFrequency(25)
                .heartbeatSocketTimeout(3000)
                .socketKeepAlive(true)
                .build());
                

也把服务器（Ubuntu）ipv4的keep alive时间改成了120秒。

但是错误还在，希望大家指教指教，谢谢！