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Accessing the Migration Report
Going to exampleyouravaloninstance.com/admin/migration_report/ will take you to this page, the Migration Report showing similar information on your migration progress.
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You'll notice as you first start importing , that all of your media objects will jump to either "Failed" or "Waiting". Media objects in "Waiting" are waiting for the "second pass" (mentioned before), which will connect them with their masterfiles and derivatives. During the second pass these object will move to either "Failed" or "Completed".
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