NetApp Certified Technology Associate (NCTA) NS0-002 Practice Test

Snapshots implement point-in-time data protection in ONTAP by using a copy-on-write mechanism with metadata references to build a space-efficient, read-only image of a volume or filesystem. When a snapshot is created, ONTAP records which blocks reflect the data at that moment and then allows writes to continue in the active dataset. The blocks that represent the snapshot’s state are preserved and referenced by the snapshot, while any subsequent changes to those blocks are written to new blocks in the active data. This sharing of unchanged blocks keeps storage use minimal and ensures the snapshot accurately represents the data as it existed at the moment of capture. It’s not about duplicating the entire volume, which would require much more space, nor about cloning for replication or simply deleting old data to reclaim space.