Symptom: RAID controller utility shows “healthy” or “optimal,” but the operating system fails to boot — or volume is missing entirely.

What This Likely Means:
In RAID 10, it’s possible for the array structure to appear “valid” at the controller level even if the underlying mirror relationships are broken. If the wrong mirror was rebuilt or the volume metadata became misaligned, the array might mount as “healthy” — but have no usable boot data.

  • Don’t try to “initialize” or “quick format” the volume — this often overwrites what’s left.
  • Avoid re-importing configs or creating a new virtual disk with the same drive layout. You may destroy access to the original.
  • Check whether any drive was marked foreign or degraded.
  • See if a prior rebuild completed or was interrupted.
  • Look in the controller logs or lifecycle viewer for errors related to volume metadata.