Cosmos Spark Connector keep loading

sopon — Thu, 17 Jul 2025 09:34:11 GMT

I am try to connect to cosmos using spark cosmos connector following this instruction: https://learn.microsoft.com/en-us/azure/cosmos-db/nosql/tutorial-spark-connector?pivots=programming-language-python.

The problem is the all spark cosmos operation keep loading and never populate any result. And I could confirm that this problem is not related to incorrect key, since I can use the same key query data from Cosmos using cosmos client python SDK.

Note: All the cloud resource including databricks workspace and cosmos are in private VNET that peers together.

Here is my code:

cfg = { "spark.cosmos.accountEndpoint" : cosmosEndpoint, "spark.cosmos.accountKey" : cosmosMasterKey, "spark.cosmos.database" : cosmosDatabaseName, "spark.cosmos.container" : cosmosContainerName } df = spark.read.format("cosmos.oltp").options(**cfg)\ .option("spark.cosmos.read.inferSchema.enabled", "true")\ .load()

Here is my cluster config:

- Databrick runtime: 13.3 LTS (includes Apache Spark 3.4.1, Scala 2.12)

- Access mode: [Legacy] Single user standard (I try using other access mode already but not working)

- Installed libs: com.azure.cosmos.spark:azure-cosmos-spark_3-4_2-12:4.37.2

Re: Cosmos Spark Connector keep loading

szymon_dybczak — Thu, 17 Jul 2025 11:33:34 GMT

Hi @sopon ,

Could you check drivers logs? Maybe we will find some useful information that will help us pinpoint root cause?
Also, you can check if you can resolve private endpoint of Comos DB from databricks workspace

$sh telnet comos_db_fqdn 433

topic Cosmos Spark Connector keep loading in Data Engineering

Cosmos Spark Connector keep loading

Re: Cosmos Spark Connector keep loading