A snapshot backup is a point-in-time copy of your data that captures the exact state of files, applications, and system configurations at a specific moment.
Unlike traditional backups that copy files individually to a separate drive, a snapshot acts like a digital “photograph” or reference map of your file system. It allows individuals and businesses to instantly roll back systems to a known-good state if they hit a snag. How Snapshot Backups Work
When you trigger a snapshot, the system does not actually duplicate all your files. Instead, it freezes the existing file structure and creates a metadata block map (a table of contents). Because it only captures pointers and settings, the initial process takes only a few seconds.
Once the snapshot is taken, the storage system tracks changes using one of two primary methods:
Copy-on-Write (COW): When a file is modified, the system pauses the action, copies the original “old data block” to a designated snapshot space, and then writes the new data over the old location.
Redirect-on-Write (ROW): Modern systems leave the original data completely untouched. New changes are written to a brand-new space on the drive, and the system updates the live pointers while the snapshot pointer keeps looking at the old blocks. The Core Benefits of Snapshots What is a Snapshot Backup? – Rubrik
Leave a Reply