Home / Computers / How can I expand the DS420+ from 4 to 9 bays?Computers Technology ramseeker nasHow can I expand the DS420+ from 4 to 9 bays?Connect a Synology DX517 expansion unit via eSATA to add 5 more drive bays, bringing the total to 9. Search Amazon As an Amazon Associate I earn from qualifying purchases.Related NotesExploreExploreExplorePrevious How does the Eufy X12 Pro compare to the Dreame X40 Ultra on hard floors?Next Henry Quick vs deep cleaner vacuums: Lightweight cordless wins for daily tidying, not deep cleans