Power BI Refresh Error:
SqlOpenConnectionTimeout

What does this error mean?

ADF or Fabric timed out opening a SQL Server connection. The server is reachable but too slow or overloaded to respond within the connection timeout.

Common causes

• 1The SQL Server is under heavy load and the connection queue is full
• 2Network latency between the integration runtime and SQL server is too high
• 3The SQL Server's max connections limit is reached
• 4A network device (load balancer, proxy) is dropping or delaying TCP SYN packets intermittently
• 5The SQL Server is in a recovery state after a restart or failover

How to fix it

1. 1Increase the connection timeout in the ADF linked service (default is usually 30s — try 90s or 120s)
2. 2Check SQL Server performance: CPU, active connections, and blocking queries in sys.dm_exec_requests
3. 3If using Azure SQL, check for DTU/vCore exhaustion in the Azure portal metrics
4. 4Move the integration runtime closer (same region) to the SQL Server to reduce network latency
5. 5Consider running the pipeline during off-peak hours if the source SQL Server is heavily loaded

Other data source errors