• Rebuild begins but stalls at 0% or a low percentage
  • No drive lights blinking to indicate activity
  • Controller still reports “Rebuilding” status
  • One of the “good” drives has unreadable sectors (silent failure)
  • The replacement drive is incompatible or incorrectly initialized
  • Controller parity verification failed but wasn’t reported
  • Don’t assume it just needs time — stalled rebuilds often never complete
  • Don’t swap in another drive without mapping original layout
  • Don’t reboot mid-rebuild — it can freeze config or corrupt metadata
  • Run SMART tests on all drives — not just the failed ones
  • Snapshot the RAID config and parity layout with JeannieLite
  • Review controller logs to pinpoint parity mismatches or I/O errors

In RAID 6, silent sector errors break parity just as fast as failed disks. Let us analyze before the controller does damage.