请注意，这段内容看起来很长，但提供了背景，并列出了我的主要问题。我研究了所有部分并包含了参考资料。
我使用Google Cloud Launcher创建Mongo数据库。这创建了两个Mongo服务器（主服务器和辅助服务器）以及一个仲裁者的副本集，分别位于三个单独的VM上。我没有更改任何VM配置（除了打开防火墙）。我已经SSH连接到了两个服务器，并验证了Mongo按预期进行了复制。我正在将外部IP从x.x.x.x更改为FIRST.EXTERNAL.IP和SECOND.EXTERNAL.IP，以使文章更易读（和安全）。
现在，我正在尝试通过Java MongoClient连接到数据库：
MongoClientOptions.Builder mongoClientOptions = MongoClientOptions.builder().connectionsPerHost(40)
.writeConcern(WriteConcern.ACKNOWLEDGED).readPreference(ReadPreference.secondaryPreferred())
.readConcern(ReadConcern.LOCAL).socketTimeout(60000).threadsAllowedToBlockForConnectionMultiplier(1500);
MongoClientURI mongoClientURI = new MongoClientURI("mongodb://FIRST.EXTERNAL.IP:27017,SECOND.EXTERNAL.IP:27017", mongoClientOptions);
mongoClient = new MongoClient(mongoClientURI);
我想确认我应该在URI中包括主要的外部IP和次要的外部IP。我没有包括仲裁者，因为MongoClient直接与仲裁者交互没有意义。
以下是尝试执行find()时出现的Java异常。Insert()创建相同的错误，只是使用WritePreferenceServerSelector而不是ReadPref..
1449 [main] INFO org.mongodb.driver.cluster - Cluster created with settings {hosts=[SECOND.EXTERNAL.IP:27017, FIRST.EXTERNAL.IP:27017], mode=MULTIPLE, requiredClusterType=UNKNOWN, serverSelectionTimeout='30000 ms', maxWaitQueueSize=60000}
1449 [main] INFO org.mongodb.driver.cluster - Adding discovered server SECOND.EXTERNAL.IP:27017 to client view of cluster
1558 [main] INFO org.mongodb.driver.cluster - Adding discovered server FIRST.EXTERNAL.IP:27017 to client view of cluster
1579 [main] INFO org.mongodb.driver.cluster - No server chosen by ReadPreferenceServerSelector{readPreference=ReadPreference{name=secondaryPreferred}} from cluster description ClusterDescription{type=UNKNOWN, connectionMode=MULTIPLE, serverDescriptions=[ServerDescription{address=SECOND.EXTERNAL.IP:27017, type=UNKNOWN, state=CONNECTING}, ServerDescription{address=FIRST.EXTERNAL.IP:27017, type=UNKNOWN, state=CONNECTING}]}. Waiting for 30000 ms before timing out
1743 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-FIRST.EXTERNAL.IP:27017] INFO org.mongodb.driver.connection - Opened connection [connectionId{localValue:2, serverValue:12}] to FIRST.EXTERNAL.IP:27017
1766 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-SECOND.EXTERNAL.IP:27017] INFO org.mongodb.driver.connection - Opened connection [connectionId{localValue:1, serverValue:9}] to SECOND.EXTERNAL.IP:27017
1790 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-FIRST.EXTERNAL.IP:27017] INFO org.mongodb.driver.cluster - Monitor thread successfully connected to server with description ServerDescription{address=FIRST.EXTERNAL.IP:27017, type=REPLICA_SET_PRIMARY, state=CONNECTED, ok=true, version=ServerVersion{versionList=[3, 4, 1]}, minWireVersion=0, maxWireVersion=5, maxDocumentSize=16777216, roundTripTimeNanos=41160155, setName='rs0', canonicalAddress=my-project-name-mongo-server-1:27017, hosts=[my-project-name-mongo-server-1:27017, my-project-name-mongo-server-2:27017], passives=[], arbiters=[my-project-name-mongo-arbiter-1:27017], primary='my-project-name-mongo-server-1:27017', tagSet=TagSet{[]}, electionId=7fffffff0000000000000003, setVersion=3, lastWriteDate=Fri Jan 27 02:30:26 PST 2017, lastUpdateTimeNanos=165366848909779}
1791 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-FIRST.EXTERNAL.IP:27017] INFO org.mongodb.driver.cluster - Discovered cluster type of REPLICA_SET
1791 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-FIRST.EXTERNAL.IP:27017] INFO org.mongodb.driver.cluster - Adding discovered server my-project-name-mongo-server-1:27017 to client view of cluster
1793 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-FIRST.EXTERNAL.IP:27017] INFO org.mongodb.driver.cluster - Adding discovered server my-project-name-mongo-server-2:27017 to client view of cluster
1794 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-FIRST.EXTERNAL.IP:27017] INFO org.mongodb.driver.cluster - Adding discovered server my-project-name-mongo-arbiter-1:27017 to client view of cluster
1796 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-FIRST.EXTERNAL.IP:27017] INFO org.mongodb.driver.cluster - Server SECOND.EXTERNAL.IP:27017 is no longer a member of the replica set. Removing from client view of cluster.
1797 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-FIRST.EXTERNAL.IP:27017] INFO org.mongodb.driver.cluster - Server FIRST.EXTERNAL.IP:27017 is no longer a member of the replica set. Removing from client view of cluster.
1798 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-FIRST.EXTERNAL.IP:27017] INFO org.mongodb.driver.cluster - Canonical address my-project-name-mongo-server-1:27017 does not match server address. Removing FIRST.EXTERNAL.IP:27017 from client view of cluster
1799 [cluster-ClusterId{value='588b214418786c23f4fcf845', description='null'}-my-project-name-mongo-server-1:27017] INFO org.mongodb.driver.cluster - Exception in monitor thread while connecting to server my-project-name-mongo-server-1:27017
com.mongodb.MongoSocketException: my-project-name-mongo-server-1: unknown error
at com.mongodb.ServerAddress.getSocketAddress(ServerAddress.java:188)
at com.mongodb.connection.SocketStreamHelper.initialize(SocketStreamHelper.java:57)
at com.mongodb.connection.SocketStream.open(SocketStream.java:58)
at com.mongodb.connection.InternalStreamConnection.open(InternalStreamConnection.java:115)
at com.mongodb.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:113)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.UnknownHostException: my-project-name-mongo-server-1: unknown error
//(then it just repeats the socket exception through connection retries I believe)
我的当前理论是，Google Cloud Launcher 最初设置的主机名配置需要使用外部IP进行更新。这意味着需要更改 my-project-name-mongo-server-1 为 FIRST.EXTERNAL.IP，第二个服务器也是同样如此，如Mongo Documentation所示。如果正确，我是否应该只保留仲裁者主机名？（顺便问一下，my-project-name-mongo-server-1:27017 是如何解析的？它是 Google Cloud 的内部IP吗？）
据我所知，这将解决我的问题和异常“Canonical address my-project-name-mongo-server-1:27017 does not match server address”。
总结一下我的问题：
1. 我应该在Java MongoClient URI中包含哪些IP？ 2. 是否应该重新配置成员主机名为外部IP？如果是，应该更改哪些？ 3. 可以选择性地解释一下 my-project-name-mongo-server-1:27017 是否是本地主机名。 4. 由于您了解我的应用程序设计，是否有更好的方法来建立外部连接？