Synology NAS Error Code 14: How to Fix It

Q: Will I lose all my data when I replace the failed drive in my Synology NAS?

Not necessarily. If your NAS uses a redundant RAID configuration such as SHR, RAID 1, or RAID 5, the system is designed to survive a single drive failure without data loss. After replacing the failed drive and initiating a repair in DSM, the array will rebuild and your data will be intact. However, if you are using a non-redundant setup (Basic or RAID 0), a failed drive typically means the data on that drive is lost unless you use professional data recovery services.

Q: How long does a Synology RAID rebuild take after replacing a drive?

RAID rebuild time depends on the drive capacity, the RAID type, and how busy the NAS is during the process. As a general estimate, expect roughly 1-2 hours per terabyte under normal conditions. A 4TB array might take 6-10 hours, while an 8TB or larger array could take 12-24 hours or more. The NAS remains usable during the rebuild, but performance will be reduced and the array remains vulnerable to a second failure until the rebuild completes.

Q: Can I use any hard drive to replace the failed drive in my Synology NAS?

You should use a drive from Synology's official compatibility list for your specific NAS model, which you can find at synology.com/compatibility. Using an unsupported drive may work, but can cause DSM warnings, compatibility issues, or instability. Always choose a NAS-rated CMR (Conventional Magnetic Recording) drive rather than SMR drives for RAID use, as SMR drives are significantly slower during RAID rebuilds and can cause timeouts and errors.

Q: What does Error Code 14 mean exactly on a Synology NAS?

Synology DSM Error Code 14 indicates that a hard drive has been detected as failed or has become unresponsive within the storage system. DSM continuously monitors drive health using S.M.A.R.T. data and I/O error rates. When a drive crosses a failure threshold — such as too many reallocated sectors, read errors, or complete unresponsiveness — DSM flags it with this critical error code and marks the affected storage pool as degraded or crashed, depending on whether the pool had redundancy.

Q: Should I replace my Synology NAS drives proactively before they fail?

Yes, proactive drive replacement is a best practice. Synology recommends monitoring S.M.A.R.T. attributes monthly using Storage Manager's scheduled S.M.A.R.T. tests and enabling DSM health notifications. If a drive shows rising counts of reallocated sectors, pending sectors, or uncorrectable sectors — even without a full failure — replace it during a planned maintenance window rather than waiting for complete failure. Most NAS drives have a manufacturer-rated lifespan of 3-5 years, and replacing drives on a rolling schedule every 4-5 years reduces unexpected failure risk.

Abstract

Synology NAS Error Code 14 is a critical alert indicating that one or more hard drives in your Synology NAS has failed or is no longer recognized by DSM (DiskStation Manager). This error requires immediate attention because continued operation risks permanent data loss, especially if your storage pool lacks redundancy. Acting quickly to identify the failed drive and replace it gives you the best chance of recovering your data intact.