Power BI Model based on Databricks Serverless SQL Warehouse refresh failure - ODBC: ERROR [HY000]

[allanw]

Hello,

We have some Power BI semantic models that are refreshed based on data from Azure Databricks, served by Serverless SQL Warehouse compute. We have Power BI VNet gateway connection set up.

It has been working well, until recently, the refreshes are failing, with error message like this...

"

Data source error: {"error":{"code":"DM_GWPipeline_Gateway_MashupDataAccessError","pbi.error":{"code":"DM_GWPipeline_Gateway_MashupDataAccessError","parameters":{},"details":[{"code":"DM_ErrorDetailNameCode_UnderlyingErrorCode","detail":{"type":1,"value":"-2147467259"}},{"code":"DM_ErrorDetailNameCode_UnderlyingErrorMessage","detail":{"type":1,"value":"ODBC: ERROR [HY000] [Microsoft][ThriftExtension] (14) Unexpected response from server during a HTTP connection: connect() failed: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.."}},{"code":"DM_ErrorDetailNameCode_UnderlyingHResult","detail":{"type":1,"value":"-2147467259"}},{"code":"Microsoft.Data.Mashup.ErrorCode","detail":{"type":1,"value":"10478"}},{"code":"Microsoft.Data.Mashup.ValueError.DataSourceKind","detail":{"type":1,"value":"Databricks"}},{"code":"Microsoft.Data.Mashup.ValueError.DataSourcePath","detail":{"type":1,"value":"{\"host\":\"adb-<xxxxxxxxxxxxxx>.<xx>.azuredatabricks.net\",\"httpPath\":\"\\/sql\\/1.0\\/warehouses\\/<xxxxxxxxxxxxxxxxxx>\"}"}},{"code":"Microsoft.Data.Mashup.ValueError.NativeError","detail":{"type":1,"value":"14"}},{"code":"Microsoft.Data.Mashup.ValueError.OdbcErrors","detail":{"type":1,"value":"#table({\"SQLState\", \"NativeError\", \"Message\"}, {})"}},{"code":"Microsoft.Data.Mashup.ValueError.Reason","detail":{"type":1,"value":"DataSource.Error"}},{"code":"Microsoft.Data.Mashup.ValueError.SQLState","detail":{"type":1,"value":"HY000"}}],"exceptionCulprit":1}}}

"

(screenshot also attached)

I wonder if anyone has ever encountered this issue? 

And what solution you have found for this?

Thank you in advance for sharing your experiences and insights!

[v-aatheeque]

Hi @allanw 

Have you had a chance to look through the responses shared earlier? If anything is still unclear, we’ll be happy to provide additional support.

[v-aatheeque]

Hi @allanw 

We wanted to follow up to check if you’ve had an opportunity to review the previous responses. If you require further assistance, please don’t hesitate to let us know.

[anilgavhane]

Note-AI helped me to format this solution.

1 Check Warehouse Status

Go to Databricks → SQL → Warehouses → Serverless warehouse.

Ensure it is running.

Disable “Auto-stop” temporarily and test refresh.

---

2.Test Connection from Gateway VM

On the machine hosting the Power BI VNet Gateway, run:

 

# test TCP connectivity telnet adb-<workspace>.azuredatabricks.net 443

If the connection fails → VNet / NSG / firewall issue.

---

3. Update ODBC Driver

Ensure Microsoft ODBC Driver for Databricks is latest version:

Databricks ODBC Driver Download

Restart the gateway after update.

---

4. Check Power BI Dataset Settings

Go to Power BI Service → Dataset → Settings → Data Source Credentials.

Re-enter Databricks credentials (PAT token or OAuth).

Ensure the VNet gateway is selected correctly.

---

5. Enable Query Logging / Monitor

In Databricks:

SQL → Query History → Check for failed / long-running queries.

Verify if the warehouse received the query request at all.

---

6. Optional: Increase Gateway Timeout

Power BI VNet gateway has a timeout setting (default ~2 minutes).

For large datasets, increase the timeout or split queries.

@allanw

[v-aatheeque · Accepted solution]

Hi @allanw ,

Thanks for reaching out to Microsoft Fabric Community Forum.

The specific error message you're seeing, ODBC: ERROR [HY000] [Microsoft][ThriftExtension] (14) Unexpected response from server, suggests that there might be connectivity issues between Power BI and your Azure Databricks SQL Warehouse.

Here are some steps and considerations that might help you resolve this issue:

• Ensure the SQL Warehouse is Running (not stopped or scaling)
• Verify Access Token used in Power BI is valid and not expired regenerate and update if needed.
• Confirm the Server Hostname and HTTP Path values are correct in the data source settings,From the gateway machine, make sure outbound HTTPS connectivity to Databricks endpoint is allowed: No firewall/proxy blocking ,Port 443 open outbound
• On the gateway machine, run an ODBC test using the same driver and token. Ensure the latest Databricks ODBC driver is installed.
• Restart the On-premises Data Gateway and ensure the data source mapping is correct and online
• Retry the dataset refresh in Power BI Service after the above validations.

Hope this helps!!

Thank You.

[sergej_og]

Hey @allanw ,
we use Azure Databricks as well in different projects.
Not sure about the Vnet gateway part...but we saw another behaviour while using serveless compared to all purpose compute.
At least for our needs we stopped using serverless because this compute seems to be in a diffenrent environment to "all purpose" compute cluster and serveless caused a lot of trouble.
Sounds a bit similar to me.

From a cost perspective it might make sense NOT to use serverless.
You can execute your sql statements with an all purpose cluster as well.

Regards