Synology NAS SHR-2 Minimum Disk Count Error: How to Fix It

Medium 30-60 minutes plus drive sync time Medium Severity Verified June 2026
Error Code
SHR-2 minimum disk count
Brand
Synology
Product Type
nas
Severity
Medium
DIY Difficulty
Medium
Estimated Fix Time
30-60 minutes plus drive sync time
The Synology SHR-2 minimum disk count error appears when you try to create an SHR-2 storage pool with fewer than 4 drives. SHR-2 (Synology Hybrid RAID 2) requires at least 4 drives to provide dual-disk redundancy, while SHR-1 only needs 2 drives for single-disk protection.
Ad

Tools You'll Need

How to Fix Error Code SHR-2 minimum disk count

  1. Check Current Drive Configuration

  2. Decide Between Adding Drives or Using SHR-1

  3. Power Down and Install Additional Drives (Option 1)

    Always power down the NAS before installing new drives. Ensure drives are compatible with your specific Synology model.
  4. Create SHR-2 Storage Pool with 4+ Drives

    Creating a new storage pool will erase all data on the selected drives. Ensure you have backups of any important data.
  5. Create SHR-1 Storage Pool Instead (Option 2)

    SHR-1 provides less protection than SHR-2 but works with fewer drives.
  6. Verify Storage Pool Creation

Parts You May Need

SATA hard drives or SSDs
Check Price on Amazon
Drive mounting screws
Check Price on Amazon
SATA hard drives or SSDs
Check Price on Amazon
Drive mounting screws
Check Price on Amazon
SATA hard drives or SSDs
Check Price on Amazon
Drive mounting screws
Check Price on Amazon
SATA hard drives or SSDs
Check Price on Amazon
Drive mounting screws
Check Price on Amazon
SATA hard drives or SSDs
Check Price on Amazon
Drive mounting screws
Check Price on Amazon
SATA hard drives or SSDs
Check Price on Amazon
Drive mounting screws
Check Price on Amazon
SATA hard drives or SSDs
Check Price on Amazon
Drive mounting screws
Check Price on Amazon
SATA hard drives or SSDs
Check Price on Amazon
Drive mounting screws
Check Price on Amazon
Ad

When to Call a Professional

Contact Synology support if drives aren't recognized after installation, if you're uncomfortable opening the NAS enclosure, or if you need help planning the optimal storage configuration for your specific use case and budget.

Frequently Asked Questions

What's the difference between SHR-1 and SHR-2?
SHR-1 provides single-drive redundancy (can survive 1 drive failure) and requires minimum 2 drives. SHR-2 provides dual-drive redundancy (can survive 2 simultaneous drive failures) and requires minimum 4 drives.
Can I convert SHR-1 to SHR-2 later?
No, you cannot directly convert between SHR types. You would need to backup your data, recreate the storage pool as SHR-2 with 4+ drives, then restore your data.
Do all drives need to be the same size for SHR-2?
No, SHR allows mixed drive sizes. However, the storage capacity is optimized based on the smallest drive in the pool. Using drives of similar sizes maximizes available storage space.
How long does SHR-2 initialization take?
Initial synchronization time depends on drive size and number. Expect 6-24 hours for 4TB drives. The NAS remains usable during this process, though performance may be reduced.
What happens if I try to create SHR-2 with only 3 drives?
The system will show the minimum disk count error and prevent creation. SHR-2 mathematically requires at least 4 drives to provide dual-parity protection.