Accidental Overwrite

Even in a cluster with data replication, important data can be overwritten or deleted accidentally. If a data set is accidentally removed, the removal itself propagates across the replicas and the data is lost. Users or applications can corrupt data, and once the corruption spreads to the replicas the damage is permanent.

Solution: Snapshots

With MapR, you can create a point-in-time snapshot of a volume, allowing recovery from a known good data set. You can create a manual snapshot to enable recovery to a specific point in time, or schedule snapshots to occur regularly to maintain a recent recovery point. If data is lost, you can restore the data using the most recent snapshot (or any snapshot you choose). Snapshots do not add a performance penalty, because they do not involve additional data copying operations; a snapshot can be created almost instantly regardless of data size.

The following sections provide examples of using snapshots to protect data: