Medium severityfabric
Power BI Refresh Error:
AzureStorageOperationFailedConcurrentWrite
What does this error mean?
Multiple concurrent Fabric Data Factory copy activities are writing to the same Blob Storage or ADLS Gen2 file simultaneously, causing a write conflict. Azure Blob Storage does not support concurrent writers to the same file path.
Common causes
- 1Multiple copy pipeline runs are active simultaneously and all target the same output file path
- 2A pipeline with parallelism enabled has multiple partitions all writing to the same sink file
- 3An external process (another pipeline, application, or script) is also writing to the same blob path while the copy activity runs
Beyond the docs
The official documentation does not cover this error — these are community-tested approaches.
- 1Ensure only one pipeline run writes to a given file path at a time — add a pipeline trigger filter or sequential execution constraint
- 2In the copy activity's sink, change the file naming pattern to include a partition index, run ID, or timestamp to generate unique file names per parallel partition
- 3Use the 'Merge files' option only when a single output file is required, and limit parallelism to 1 for that activity
- 4Check for other pipelines or applications that might be writing to the same path and coordinate their schedules
Official documentation: https://learn.microsoft.com/en-us/fabric/data-factory/connector-troubleshoot-azure-blob-storage