Technical reference library

First-party technical reference tables from the WeRecoverData laboratories: failure symptoms and causes, RAID levels, ZFS RAID-Z parity levels, SSD recoverability, and media handling.

• Failure symptoms, likely cause, and recoverability

  First-party reference table mapping observable storage failure symptoms to their likely cause, the correct first action, and how recoverability is affected.

• RAID levels reference

  First-party reference covering every common RAID level: layout, minimum drives, usable capacity, fault tolerance, rebuild risk, and relative data recovery difficulty.

• SSD recoverability matrix

  First-party reference explaining what is and is not recoverable from an SSD, covering TRIM, garbage collection, wear levelling, self-encrypting drives, and controller failure.

• Media handling: what helps, what destroys data

  First-party reference listing the actions that preserve recoverability after data loss and the common actions that permanently reduce it, by media type.

• RAID-Z, RAID-Z2 and RAID-Z3: how ZFS parity levels differ

  First-party reference on ZFS RAID-Z: how single, double and triple parity differ in fault tolerance, usable capacity, resilver exposure, and what each means for data recovery.

See also the glossary, myths and corrections, and the company fact sheet.