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sqlsql-serverazureazure-sql-databasedata-migration

Azure SQL Data Migration Assistant is Stuck on “Migrate Data”


I am in the process of using the Data Migration Assistant to move a local DB to Aszure SQL. The schema transfer went well, and 243 of the 246 tables all were able to transfer their data with no errors.

However, the transfer has been running for 13+ hours, and over the last three hours, three of the tables have not budged on their percent complete. One is at 92.3%, one is at 93.9%, and the last is at 98.5%.

Some questions:

  • At this point, can I safely assume that this is a failed transfer, at least of these three tables?
  • I don't see a "stop" button. If I wanted to, how would I abort this process?
  • If I were to abort the process, is there some way to manually finish the transfer of data from just these three tables?

Solution

  • A Microsoft Engineer examined the logs you shared with us and found the following error:

    Dma.exe Information: 0 : 'Exception type: System.IO.IOException Message: There is not enough space on the disk.

    It seems like workstation that DMA is running on doesn’t have enough disk space to do schema extract.

    The following is the explanation the Microsoft engineer shared with us about why DMA requires disk space:

    The Extract service connects to a database, reads all of its objects and their properties, and then creates an in-memory model of the database. Similar to how the Build service validates the defined objects, the Extract service also checks for consistency and containment. The validation done here will also result in failures if you have a view that refers to a non-existent table same as with T-SQL! Additionally, unsupported or uncontained objects are blocked because these objects are not yet allowed in SQL Azure or the DAC in-memory model. Finally, once the in-memory model is complete and validated, a DACPAC is written to disk. Looking at the stack it’s a well-known Windows exception on not enough disk space.