Mistake 1: Sizing on raw capacity instead of effective capacity
Root Cause
Procurement processes that evaluate storage on raw TB rather than effective TB after data reduction. Vendor data reduction claims are accepted without verification.
Consequence
Arrays that run out of effective capacity before expected, requiring emergency capacity additions at premium pricing.
Prevention
Require proof-of-concept testing with actual production data to verify data reduction ratios before procurement. Size on verified effective capacity.
Mistake 2: Using a single storage tier for all workloads
Root Cause
Standardizing on a single storage platform for all workloads, either all-flash (expensive for cold data) or spinning disk (inadequate for hot data).
Consequence
Either overspending on high-performance storage for cold data, or performance problems on hot data that require emergency remediation.
Prevention
Design a tiered storage architecture: NVMe all-flash for hot data, SSD or hybrid for warm data, high-capacity HDD or object storage for cold data.
Mistake 3: Inadequate data protection scheme
Root Cause
Using RAID 5 for large-capacity drives, or relying on RAID alone without replication and snapshots.
Consequence
RAID 5 rebuild failures on large drives are common, the probability of a second drive failure during rebuild is significant. Data loss events that RAID alone cannot prevent.
Prevention
Use RAID 6 minimum for enterprise arrays. Implement replication and snapshots in addition to RAID. Test recovery regularly.
Mistake 4: Treating backup as the only data protection
Root Cause
Organizations that implement backup but not replication or snapshots, assuming that backup is sufficient for all data protection scenarios.
Consequence
Backup recovery times (hours to days) are inadequate for mission-critical workloads. Ransomware that targets backup systems prevents recovery.
Prevention
Implement a complete data protection strategy: RAID for drive failure, snapshots for corruption and accidental deletion, replication for site failure, and immutable backup for ransomware.
Mistake 5: Not testing recovery
Root Cause
Organizations that implement backup and replication but never test recovery, assuming that the protection works because it was configured correctly.
Consequence
Backup and replication configurations that appear to work but fail during actual recovery. Recovery times that are far longer than the stated RTO.
Prevention
Test recovery quarterly for all workloads. Test full DR failover annually. Document recovery procedures and verify that the operations team can execute them.
Mistake 6: Ignoring storage network requirements
Root Cause
Deploying high-performance storage (NVMe all-flash) on a network that cannot deliver the throughput the storage is capable of.
Consequence
NVMe storage that delivers spinning-disk performance because the network is the bottleneck. The performance investment in the storage array is wasted.
Prevention
Size the storage network for the throughput the storage array can deliver. NVMe-oF requires 100 GbE minimum. Verify network performance before deploying storage.
The common thread