MongoDB connection setup: unable to find valid certification path

Looks like (from the server.log) the MongoDB connection plugin is not finding a valid certification path. Any ideas how I can set this?

2019-05-12 02:21:38,412 [Plugin Startup: Test] ERROR c.d.p.mongo.MongoDocumentHelper - Mongo command returned with invalid return code (not OK), Could not authenticate user my_read_only_user for database my_db : { “Exception” : “com.mongodb.MongoTimeoutException: Timed out after 2000 ms while waiting for a server that matches com.mongodb.Mongo$4@a09b709. Client view of cluster state is {type=REPLICA_SET, servers=[{address=my_mongo_host.domain.com:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketWriteException: Exception sending message}, caused by {javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target}, caused by {sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target}, caused by {sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target}}]” }

@noah, please describe your mongo instance in more detail. Are you connecting to a replica set? Have you enabled TLS on the Mongo cluster? What extra parameters have you added (if any) to the Mongo source configuration in Dremio?