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JDT
Frequent Visitor

Tcp Error Dataflow Gen2 - Rest API to Warehouse

Hi,

 

we always get the following error message when we try to add a destination (Warehouse and Lakehouse) to our dataflow:

 

Something went wrong while retrieving the list of tables. Please try again later.: An exception occurred: Microsoft SQL: A connection was successfully established with the server, but then an error occurred during the pre-login handshake. (provider: TCP Provider, error: 0 - The semaphore timeout period has expired.) (Session ID: 3febcc13-7756-427d-b213-973978a414a4, Region: europe)

 

Or it errors out with Unknown Error

 

The dataflow reads some data from REST APIs - everything seems fine in the preview. No on-prem gateway is involved.

JDT_0-1728978222971.png

Any tips ?

2 REPLIES 2
frithjof_v
Super User
Super User

Does it work if you use another Dataflow to query the first Dataflow, and write to destination?

 

I.e. API -> Dataflow -> Dataflow -> Destination

lbendlin
Super User
Super User

No on-prem gateway is involved

You would think that.  But that's not how they set it up.

 

Configure proxy settings for the on-premises data gateway | Microsoft Learn

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