Error while connecting MongoDB as source to Kafka

Question

I am trying to connect MongoDB as source to Kafka server but when I run Debezium Mongo source connector, I get error. I don't understand why timed out?

[2019-08-22 13:28:58,194] INFO Cluster description not yet available. Waiting for 30000 ms before timing out (org.mongodb.driver.cluster:71)
[2019-08-22 13:28:58,648] INFO Exception in monitor thread while connecting to server morgan-shard-00-00-ayfai.mongodb.net:27017 (org.mongodb.driver.cluster:76)
com.mongodb.MongoSocketReadException: Prematurely reached end of stream
    at com.mongodb.internal.connection.SocketStream.read(SocketStream.java:112)
    at com.mongodb.internal.connection.InternalStreamConnection.receiveResponseBuffers(InternalStreamConnection.java:554)
    at com.mongodb.internal.connection.InternalStreamConnection.receiveMessage(InternalStreamConnection.java:425)
    at com.mongodb.internal.connection.InternalStreamConnection.receiveCommandMessageResponse(InternalStreamConnection.java:289)
    at com.mongodb.internal.connection.InternalStreamConnection.sendAndReceive(InternalStreamConnection.java:255)
    at com.mongodb.internal.connection.CommandHelper.sendAndReceive(CommandHelper.java:83)
    at com.mongodb.internal.connection.CommandHelper.executeCommand(CommandHelper.java:33)
    at com.mongodb.internal.connection.InternalStreamConnectionInitializer.initializeConnectionDescription(InternalStreamConnectionInitializer.java:106)
    at com.mongodb.internal.connection.InternalStreamConnectionInitializer.initialize(InternalStreamConnectionInitializer.java:63)
    at com.mongodb.internal.connection.InternalStreamConnection.open(InternalStreamConnection.java:127)
    at com.mongodb.internal.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:117)
    at java.lang.Thread.run(Thread.java:748)
[2019-08-22 13:29:08,196] INFO Created connector mongodb-source-connector (org.apache.kafka.connect.cli.ConnectStandalone:112)
[2019-08-22 13:29:28,195] ERROR Error while reading the 'shards' collection in the 'config' database: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=morgan-shard-00-00-ayfai.mongodb.net:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketReadException: Prematurely reached end of stream}}] (io.debezium.connector.mongodb.ReplicaSetDiscovery:80)
com.mongodb.MongoTimeoutException: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=morgan-shard-00-00-ayfai.mongodb.net:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketReadException: Prematurely reached end of stream}}]
    at com.mongodb.internal.connection.BaseCluster.getDescription(BaseCluster.java:179)
    at com.mongodb.internal.connection.SingleServerCluster.getDescription(SingleServerCluster.java:41)
    at com.mongodb.client.internal.MongoClientDelegate.getConnectedClusterDescription(MongoClientDelegate.java:136)
    at com.mongodb.client.internal.MongoClientDelegate.createClientSession(MongoClientDelegate.java:94)
    at com.mongodb.client.internal.MongoClientDelegate$DelegateOperationExecutor.getClientSession(MongoClientDelegate.java:249)
    at com.mongodb.client.internal.MongoClientDelegate$DelegateOperationExecutor.execute(MongoClientDelegate.java:172)
    at com.mongodb.client.internal.MongoIterableImpl.execute(MongoIterableImpl.java:132)
    at com.mongodb.client.internal.MongoIterableImpl.iterator(MongoIterableImpl.java:86)
    at com.mongodb.client.internal.MappingIterable.iterator(MappingIterable.java:39)
    at io.debezium.connector.mongodb.MongoUtil.contains(MongoUtil.java:183)
    at io.debezium.connector.mongodb.MongoUtil.contains(MongoUtil.java:172)
    at io.debezium.connector.mongodb.MongoUtil.onDatabase(MongoUtil.java:116)
    at io.debezium.connector.mongodb.MongoUtil.onCollection(MongoUtil.java:131)
    at io.debezium.connector.mongodb.MongoUtil.onCollectionDocuments(MongoUtil.java:150)
    at io.debezium.connector.mongodb.ReplicaSetDiscovery.getReplicaSets(ReplicaSetDiscovery.java:67)
    at io.debezium.connector.mongodb.ReplicaSetMonitorThread.run(ReplicaSetMonitorThread.java:65)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)
[2019-08-22 13:29:28,195] INFO Cluster description not yet available. Waiting for 30000 ms before timing out (org.mongodb.driver.cluster:71)
[2019-08-22 13:29:58,196] ERROR Error while trying to get information about the replica sets (io.debezium.connector.mongodb.ReplicaSetMonitorThread:87)
com.mongodb.MongoTimeoutException: Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=morgan-shard-00-00-ayfai.mongodb.net:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketReadException: Prematurely reached end of stream}}]
    at com.mongodb.internal.connection.BaseCluster.getDescription(BaseCluster.java:179)
    at com.mongodb.internal.connection.SingleServerCluster.getDescription(SingleServerCluster.java:41)
    at com.mongodb.Mongo.getClusterDescription(Mongo.java:412)
    at com.mongodb.Mongo.getReplicaSetStatus(Mongo.java:455)
    at io.debezium.connector.mongodb.ReplicaSetDiscovery.getReplicaSets(ReplicaSetDiscovery.java:85)
    at io.debezium.connector.mongodb.ReplicaSetMonitorThread.run(ReplicaSetMonitorThread.java:65)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)

Answer 1

Without looking at the connector configuration it would be impossible to know the exact issue but from my experience with MongoDB Atlas and Debezium, it can be an issue with SSL.

Try enabling SSL

mongodb.ssl.enabled: true

https://debezium.io/documentation/reference/1.2/connectors/mongodb.html#mongodb-property-mongodb-ssl-enabled