Your RAID 60 Shows “Healthy Drives”… but No Volume. What’s Actually Happening?
When a RAID 60 volume disappears — even though every disk reports Online — the root cause is rarely a drive problem.
In RAID 60, this symptom almost always means:
The two RAID-6 groups no longer agree on:
- parity position
- stripe-set sequence
- metadata generation state
- foreign-config identity
When the controller detects any cross-group disagreement, it hides the array instead of guessing.
This is expected behavior.
It protects your data from being overwritten by a bad import or rebuild.
1. What This Failure Really Means (Plain English)
Your disks didn’t fail.
Your math did.
One RAID-6 group advanced farther than the other — sometimes by only a few stripes — and the controller refuses to mount a virtual disk that cannot be assembled deterministically.
This creates the classic RAID-60 symptom:
** Drives: GOOD
✘ Array: NOT PRESENT**
This is why no volume appears, even in the controller BIOS.
2. Why RAID 60 Fails This Way (The Real Cause)
Most common root causes:
- Cross-Group Parity Divergence
One group committed writes that the other never completed. - Staggered Stripe-Set Failure
Mixed-age disks or different URE behavior cause stripe sets to desync. - Silent Parity Mismatch
No SMART warning. No noise. No error.
Just math that no longer validates. - Foreign Config Asymmetry After Reboot
Group A and Group B present mismatched timestamps/sequence numbers.
These conditions are described in detail in your Technical Note:
TN-R60-001
https://www.adrdatarecovery.com/raid-triage-center/technical-note-tn-r60-001/
3. Why Your Data Isn’t Gone (Yet)
If the controller can’t assemble the two groups into a coherent stripe layout, it refuses to mount the virtual disk.
This prevents:
- overwriting valid parity with mismatched data
- launching a destructive rebuild
- importing a corrupt foreign config
- zeroing mismatched metadata
The controller is protecting your data from you.
<h3>Diagnostic Overview</h3>
<ul>
<li><strong>Device:</strong> RAID 60 array (two RAID-6 groups under RAID-0)</li>
<li><strong>Observed State:</strong> All drives “Online” — Virtual Disk missing/unmountable</li>
<li><strong>Likely Cause:</strong> Cross-group inconsistency or foreign-config mismatch</li>
<li><strong>Do NOT:</strong> Import foreign configs, force mount, or launch rebuild</li>
<li><strong>Recommended Action:</strong> Clone all drives, extract both groups’ metadata, virtualize groups independently, then align parity domains offline</li>
</ul>
5. Symptom → Meaning → Correct Action
SYMPTOM 1 — Drives Good, VD Missing
Meaning: Parity-domain disagreement
Correct Action: Offline group extraction & virtualization
SYMPTOM 2 — Controller Shows “Foreign Config Detected”
Meaning: Groups disagree on prior state
Correct Action: Do not import; image all drives
SYMPTOM 3 — Volume Seen in OS, but Won’t Mount
Meaning: Stripe-set offset between Group A and Group B
Correct Action: Reconstruct stripe alignment offline
SYMPTOM 4 — After Drive Swap, Volume Vanished
Meaning: Staggered commit left one group ahead of the other
Correct Action: Inspect metadata generations on both groups
6. How ADR Recovers This Safely
ADR’s RAID Inspector™ performs:
Step 1 — Deep Metadata Extraction
Per-disk, per-group, not trusting controller logic.
Step 2 — Group Isolation & Virtualization
Each RAID-6 group is rebuilt virtually, not on the controller.
Step 3 — Parity-Domain Comparison
Detects which group advanced farther.
Step 4 — Controlled Alignment
Mathematically re-unifies the arrays without destructive writes.
Step 5 — File System Validation
Ensures no surprises: wrong-size files, missing extents, incomplete commits.
This is the only safe way to recover RAID 60.
7. Summary
Your RAID 60 didn’t disappear because disks failed.
It disappeared because your two parity domains stopped agreeing — a mismatch your controller won’t risk assembling incorrectly.
Recovery is possible, but only by extracting both groups, rebuilding them virtually, and realigning the math offline.
RAID Triage Center – RAID 60 Triage – RAID 60 Technical Notes