Expansion

Plan drive replacement before buying larger disks

Before buying a single larger drive, model the target layout and verify the platform’s rules for when extra capacity becomes usable.

Model the end state

Write down every current drive size, the proposed replacements, the intended pool layout, and the free bays. Do not infer the result from one replacement alone.

Verify platform rules

Synology, ZFS-based systems, and Unraid have different expansion behavior. Follow the official documentation for the exact release and platform.

Protect before migration

Confirm independent recovery copies and drive health before a replacement sequence. Expansion is a change operation, not just a shopping task.

Continue planning

Turn this storage question into a capacity baseline.

Use the planner to make growth, bays, redundancy, and recovery capacity visible together.

Build a storage plan

Hardware shape

Choose NAS drive bays from the next expansion

Recovery

Use RAID for availability, not as the only backup

Degraded operation

Estimate a NAS rebuild window before a drive fails

Editorial record

Maintained by Make Your Own Tools to turn “Store data safely” into a defined capacity, bays, redundancy, and recovery baseline. The references below provide the technical context for this planning path. Its calculation rules and planning assumptions are documented in the methodology, and affected calculations pass regression checks before the review date advances.

Last reviewed
Evidence set
2 primary references
Calculation coverage
2 affected rules checked
Read methodology →View change history ↗
Planning scope
Planning a replacement or expansion path before purchasing drives.
Next check
Carry the modeled end state into the target platform’s capacity calculator, compatibility list, and expansion procedure.
Synology drive replacement and expansion guidancePlatform-specific conditions for capacity changes after drive replacement.Open source ↗TrueNAS ZFS Capacity CalculatorZFS capacity, redundancy, and configuration-planning reference.Open source ↗