NAS RAID Degraded: What to Do

A degraded RAID array still works, which is why it is dangerous. Here is a calm step-by-step response.

What degraded means

The array has lost a member disk but still serves data using redundancy. Protection is reduced or gone until the disk is replaced and the array rebuilt.

Steps to take

1. Do not panic and do not power off unless the device advises.
2. Check that a recent backup exists, and make one if not.
3. Identify the failed disk and bay from the NAS interface or your monitoring dashboard.
4. Replace it with a compatible disk of equal or larger size.
5. Let the rebuild finish and avoid heavy workloads.
6. Verify the array returns to healthy and check other disks.

Common mistakes

• Pulling the wrong disk
• Ignoring the alert for weeks
• Having no backup
• Using mismatched or unsuitable disks

Get notified sooner

With RAID monitoring an alert arrives at the moment the array degrades.

RAID Monitoring Software for NASNAS Configuration Management SoftwareSNMP NAS Monitoring SoftwareNAS Monitoring Software in NoidaNAS Capacity Planning GuideSNMP Monitoring for NAS: A Practical GuideNAS vs SAN vs DAS: Differences ExplainedNAS Backup and the 3-2-1 Rule

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