What Are the Differences Between Backups and Snapshots?¶
Both backups and snapshots provide data redundancy for EVS disks to improve data reliability. Table 1 lists the differences between them.
Technology | Saved In | Synchronization | DR Range | Service Recovery |
|---|---|---|---|---|
Backup | Backup data is stored in OBS, instead of EVS disks. This realizes data restoration upon EVS disk data loss or corruption. | A backup is the data copy of an EVS disk at a given point in time. VBS provides automatic backup by configuring backup policies. Deleting an EVS disk will not clear its backups. | A snapshot and its source EVS disk reside in the same AZ. | Data can be recovered and services can be restored by restoring the backup data to original disks or creating new disks from backups, ensuring superb data reliability. |
Snapshot | Snapshot data is stored with EVS disk data. Note Creation of and rollback to snapshots are faster than creation of and restoration from backups, because the latter requires data migration that consumes extra time. | A snapshot is the state of an EVS disk at a specific point in time. When you delete an EVS disk, the snapshots of the EVS disk are also deleted. | A snapshot and its source EVS disk reside in the same AZ. | You can use a snapshot to roll back its original EVS disk or create an EVS disk for data restoration and service recovery. |