Jose Manuel Jurado Diaz works around an issue with sqlpackage:
We used to have cases when our customers are trying to export their database using SQLPackage or Export service in the Portal having, for example, the following error message: Error SQL71562: Error validating element Synonym: [dbo].[MyView] has an unresolved reference to object [linkedserver].[databasename].[schemaname].[tablename].External references are not supported when creating a package from this platform. In this post I would like to suggest an alternative to export this data.
Read on to see what sqlpackage does not support, how you might solve it, and Eitan Blumin’s very good comment.