Key Summary & Action Items
1. Secure Your Data
Complete either a Local OR Cloud backup before any hardware is touched.
2. Permanent Safety
Cloud backup is recommended regardless to protect against theft/fire.
3. DIY Execution
Manage the swap in-house to avoid fees during multi-day system repairs.
4. Storage Target
Replacing 2 x 12TB drives increases your usable space from 12TB to 18TB.
Implementation Strategy
The bulk of this upgrade involves waiting for automated data transfers and background system "repairs" that can take several days. To avoid unnecessary professional service fees for idle system processing time, we recommend you manage the physical drive swaps and software prompts in-house using the technical framework below.
The Backup Strategy
Hardware upgrades on a system at 99% capacity are high-risk. Before any drive is removed, you must verify you have a complete copy of your data. You have two primary methods for this:
Choice A: Local Physical
Fastest for ProjectConnect a high-capacity external desktop drive via USB. This is the quickest way to secure a "local" copy before starting the drive swap, acting as a lifeline if a drive fails during the upgrade.
Estimated Transfer: 24-48 hours via direct connection.
Choice B: Off-site Cloud
Permanent ProtectionA "set and forget" upload to Synology C2 or Backblaze B2. We recommend this regardless of the upgrade to protect against theft, fire, or flood. If the office is compromised, your data remains safe.
Efficiency Tip:
Increasing your ISP upload speed temporarily will significantly reduce the initial 12TB sync time, potentially completing it in just a few days.
Staged Upgrade: 2 x 12TB Pair Swap
In a RAID 10 configuration, drives are mirrored in matched pairs. To increase usable space, you must replace both drives in a specific pair. Replacing only one drive will replace the hardware but will not unlock new storage space.
Swap First Drive
Physically pull one 6TB drive from the identified pair and insert the first 12TB. In the Synology DSM software, open Storage Manager and trigger the "Repair" process.
Monitor Repair Status
Crucial: The NAS must rebuild the safety net. You must wait until the status returns to Healthy in Storage Manager before proceeding. This time depends on current system workload.
Swap Second Drive
Pull the remaining 6TB drive from the same pair and insert the second 12TB. Repeat the "Repair" process and monitor until the status is again Healthy.
Anticipated Outcome
Old Drive Usage
The two removed 6TB drives are still functional. Placing them in external USB enclosures allows them to serve as high-capacity "shuttle" drives for large project handovers or local off-site archives.
Rebuild Stress Warning
During a RAID repair, your old drives work at 100% capacity for an extended period. If an aging drive has a hidden mechanical fault, this stress can cause a total failure. Verify your backup integrity before pulling any drive.
The Rule of One
Never remove a second drive while the system is "Repairing." The system is only safe to modify when the Storage Manager explicitly shows a Healthy status. Pulling two drives at once will result in immediate data loss.
Moving Forward
By following this staged DIY approach, you can manage the upgrade cost-effectively. The immediate priority is securing your data via a local or cloud backup. Regardless of the upgrade, establishing a permanent off-site cloud sync is vital for long-term agency safety.