Built on original basic snapshot features, ECS Snapshot 2.0 data backup service provides a higher snapshot quota and more flexible automatic task policies, further reducing its impact on business IO. The features of ECS Snapshot 2.0 are described in the following table.
|Feature||Original snapshot specifications||Snapshot 2.0 specifications||User benefit|
|Snapshot quota||(Number of disks)*6+6||64 snapshots for each disk||Longer protection circle
Smaller protection granularity
|Automatic task policy||Hardcoded, triggered once daily, and unmodifiable||Customizable weekly snapshot day, time of day, and snapshot retention period
Query-able disk quantity and related details associated with an automatic snapshot policy
|More flexible protection policy|
|Implementation principle||COW (Copy-on-write)||ROW (Redirect-on-write)||Mitigated performance impact of the snapshot task on business IO write|
The implementation of ECS Snapshot 2.0 features is described in the following table.
|Snapshot quota||Snapshot backup of a data disk for non-core businesses occurs at 00:00 every day. This backup data is retained for over 2 months.
Snapshot backup of a data disk for core businesses occurs every 4 hours. This backup data is retained for over 10 days.
|Automatic task policy||A user can take snapshots on the hour and for several times in a day.
A user can choose any day as the recurring day for taking weekly snapshots.
A user can specify the snapshot retention period or choose to retain it permanently (When the maximum number of automatic snapshots has been reached, the oldest automatic snapshot will be deleted).
|Implementation principle||The implementation principle is not made visible to users, allowing snapshots to be taken at any time of day without affecting user experience.|