SYMPTOM
“RAID 50 just dropped offline — but every drive shows green.”
“No failed drives, no errors — why is the array down?”
You’re staring at a RAID 50 array that suddenly dropped offline or became unmountable, yet every physical drive appears healthy.
The RAID controller sees all drives present. SMART data may show no errors. But the volume is inaccessible or degraded — and you’re left wondering why a system that looks fine is suddenly failing.
WHAT’S REALLY HAPPENING
RAID 50 is composed of multiple RAID 5 sets striped together.
Even if all drives are physically present, the array can fail due to:
- Logical corruption inside one stripe group
- Parity mismatches from unlogged writes or dirty shutdowns
- Metadata damage at the controller or array level
- Drive reordering (even if subtle) — just one drive moved out of order breaks parity
What’s worse: standard controller tools often hide the real issue, reporting drives as “online” when parity is mathematically invalid. It’s like looking at puzzle pieces that all exist — but no longer fit.
SMART health alone is not enough. What you need is deep validation at the array logic layer — and standard recovery tools can’t provide that.
WHAT NOT TO DO
❌ Don’t rebuild just because all drives look healthy
❌ Don’t delete and recreate the array — that overwrites metadata
❌ Don’t try a “quick format and restore” without verifying parity first
Many admins assume this is a controller glitch and attempt a fast fix:
- Reinitializing the array (erases layout map)
- Accepting a controller’s “make consistent” prompt (forces parity rebuild)
- Rebooting into RAID BIOS and reshuffling drives to “see what works”
Each of these actions increases damage to already misaligned parity or corrupts what might be recoverable.
WHEN TO ESCALATE
This is a textbook case for escalation.
Call ADR if:
- You see zero physical drive failures, but the volume won’t mount
- Your controller reports “Ready” or “Online” for all drives — yet the array is inaccessible
- You’re considering deleting and recreating the virtual disk
Our RAID Inspector™, powered by IntelliCore Logic™, goes far beyond surface-level drive checks. We run deep forensic-level tests to:
- Validate actual parity relationships
- Reconstruct the logical layout across all stripe groups
- Flag mismatch patterns invisible to your controller
Even one misaligned bit in a RAID 50 array can lead to full-volume corruption. We catch that before any irreversible actions are taken.
Looks healthy doesn’t mean safe. Let’s verify.
Run JeannieLite™ — our RAID diagnostic tool built with RAID Inspector™ intelligence.
- No install. No guesswork.
- Visual parity map in minutes.
- Flags silent corruption and logic misalignment before you make a move.