[otrs] Article Storage Type

Hello, we startet with otrs and Article attachments are stored in the DB until now. Of course the db is growing and growing we have about 10GB of DB and a backup takes ages ... Can i now switch to FS based storage and keep the articles until now in the DB? I have already tried to run the migration script from DB to FS. This fails with a few articles. Can i just skipp those and carry on? So at the end the failed articles will remain in the DB and the rest will be FS? Thanks a lot, mario