Data Protection
This domain tests local and platform-level protection: what each mechanism actually protects against and what it costs.
Layers
Availability features keep data online; protection features keep recoverable copies. At the array, HyperSnap creates point-in-time snapshots using copy-on-write, consuming space only for changed blocks; HyperClone makes a full independent copy; HyperCopy performs offline LUN copies; HyperReplication ships changed data to a remote array synchronously or asynchronously. Consistency groups freeze multi-LUN applications together so the resulting copy is crash-consistent.
Platform protection
Huawei arrays add WORM retention so copies cannot be altered or deleted before expiry, and ransomware detection that watches write patterns and entropy, then triggers snapshots or alarms. Backup copies belong on a separate system such as OceanProtect, ideally with an air gap and immutable retention.
Worked example
A DBA needs a 5 TB production copy three times a day for a 30-minute test that is then discarded. Reloading a 5 TB full clone three times daily consumes about 15 TB of capacity per day and hours of copy time. Snapshots answer better: take a snapshot, map it to the test host as a writable copy-on-write clone, run the test, unmap and delete. Only blocks the test writes are consumed. Reserve full clones for copies that must survive snapshot space exhaustion.
Traps
Calling a snapshot a backup when both copies live on the same failed array; letting snapshot space exhaust so older snapshots are invalidated; skipping consistency groups for multi-LUN databases; assuming WORM retention can be shortened after the fact; confusing differential (against the last full) with incremental (against the last backup of any kind).