How to Choose Drives for a Synology NAS

Why Drive Selection Matters for Synology

Synology NAS systems are built for reliability, but they're only as reliable as the drives inside. Choosing the wrong drives can lead to data loss, system crashes, and expensive recovery attempts. This guide walks through everything you need to know to make the right choice.

Use NAS-Optimized Drives (Not Desktop Drives)

The most important rule: Always use NAS-rated drives in your Synology. NAS drives are engineered for 24/7 operation and RAID environments. Desktop drives (Seagate Barracuda, WD Blue) can work but have much higher failure rates in continuous-use scenarios.

Avoid SMR Drives Entirely

SMR (Shingled Magnetic Recording) drives are a tragedy for RAID arrays. They're slower during rebuilds and can cause system instability. Synology itself has warned users about SMR compatibility issues. Always verify that your drives are CMR before purchasing. See our CMR vs SMR guide for the full breakdown, and our SMR RAID failure article for real-world examples.

Plan Your Capacity

For a 4-bay Synology with RAID 6 protection, here are realistic capacity targets. Use our RAID calculator to model any configuration:

Match Drives by Capacity and Model

For best results, all drives in a RAID array should be:

• The same capacity (e.g., all 4TB, not mixed 4TB and 6TB)
• The same model or series (e.g., all WD Red Plus)
• Ideally from the same production batch (same firmware version)

Plan Your Capacity

For a 4-bay Synology with RAID 6 protection, here are realistic capacity targets:

Final Checklist

• ✓NAS-rated drive (WD Red Plus, IronWolf, N300, Ultrastar)
• ✓CMR technology (not SMR)
• ✓Same capacity and model across all bays
• ✓Capacity that suits your needs with 2-3 years of growth