Running out of disk space mid-restore A colleague of mine reported that an hour after starting a restore the operation failed because the server ran out of disk space.  He mentioned that since we are using filestream the size isn't included in the backup size.

Does this sound right?  I thought the first thing sql server did up on restoring was to check the amount of disk necessary [including filestream objects] then reserve the space on disk, start initializing the allocated disk space and finally write out the data.  I didn't think it was possible to run out of disk space mid-restore.

Does any of this sound right?  Does anyone know of a reason the restore would fail halfway through?
I have not tested it, but I would think the filestream file should be included in the size.


  For example, you can use all backup and recovery models with FILESTREAM data, and the FILESTREAM data is backed up with the structured data in the database.


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In addition, it sounds like you have emtpy pages.


  Note that the backup size does not include empty pages, but when you actually perform the restore, the data and log files will be over 200 GB, because it has to restore exactly what the source system had (including a 200+ GB log file, regardless of how full it was). 


Your example may not be 200+GB, but it was in the case for this person when their backup was pretty small.

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