Enterprise arrays bundle premium hardware with capacity-based software licensing and costly controller upgrades. Software-defined and open targets — TrueNAS (ZFS), Ceph (block/file/object), MinIO (object) — run on commodity hardware and remove the per-TB software tax, in exchange for more design and operational ownership.
Choosing a target
- TrueNAS — ZFS NAS/SAN, strong for file/iSCSI with snapshots and replication; simplest path for many estates.
- Ceph — unified block (RBD), file (CephFS), and object (RGW); scale-out and self-healing, but more to operate.
- MinIO — S3-compatible object storage for cloud-native and backup targets.
Plan the data path
Inventory LUNs/volumes/shares, capacity, IOPS/throughput, snapshots, and replication/DR relationships. Confirm host connectivity (FC/iSCSI/NFS) and multipathing to the target. Provision for performance, not just capacity — match IOPS/latency, plan N+1 redundancy, and budget snapshot/replication overhead (often 20–30%).
Migration mechanics
Migrate data by host-level copy (rsync for files, preserving permissions/sparseness), storage vMotion, or array/target replication. Re-present LUNs/shares from the target, update mounts/initiators, and rescan/verify multipath. For object workloads, sync with rclone/mc.
Cutover & validation
Quiesce host I/O (or use online replication), run a final sync, re-present, and validate capacity, IOPS, and latency against baseline. Run a path-failure / controller-failover test and a snapshot/replication/DR test, plus data-integrity verification, before retiring the source array. Roll back by re-presenting the original LUNs if validation fails.
De-risking
Test a single LUN/share end-to-end first, then migrate host-group by host-group in maintenance windows. Keep the source array available as fallback through hypercare.
Open a source→target page for tier recommendations and a TCO model sized on usable TB.