# Four-drive Windows-format USB pretest health

Status: complete
Type: evidence
Updated: 2026-08-01
Next Action: none; retain as historical pretest evidence for the completed broad matrix

Project Map: work/maps/map-smi-firmware-stabilization-and-qualification.md
Workpackage: work/wp/completed/wp-restore-broad-usb-compatibility-baseline.md

## Owner-selected baseline

The owner selected these four freshly Windows-formatted USB drives as the
upfront Stage 1B baseline:

| Canonical label | Pi device during check | Model / identity | Capacity | FAT UUID |
| --- | --- | --- | ---: | --- |
| `USB01_2G` | `/dev/sda` | USB DISK 2.0 / `_USB_DISK_2.0-0:0` | 2,013,265,920 bytes | `D45F-70AA` |
| `USB05_4G` | `/dev/sdb` | General UDisk / descriptor serial unavailable; Linux fallback `General_UDisk-0:0` | 4,026,531,840 bytes | `362E-8170` |
| `USB02_8G` | `/dev/sdc` | General UDisk / `1003112253528015858612` | 8,053,063,680 bytes | `D499-DF4E` |
| `USB03_32G` | `/dev/sdd` | PNY USB 2.0 FD / `071C49DE25C08808` | 31,042,043,904 bytes | `BCE4-0E61` |

Linux device names are session-local; canonical labels and valid hardware
identities govern later movement and attribution.

## Read-only checks

- All four devices enumerated as removable USB Mass Storage devices with one
  MBR partition bounded within reported capacity.
- All four partitions identified as FAT32 and remained unmounted throughout.
- `fsck.fat -n -v` reached the last filesystem sector, found two consistent
  FATs, and reported no lost clusters, cross-links, or structural corruption.
- Windows stored each volume label in the root directory while leaving the
  boot-sector label field blank. `fsck.fat` proposed copying the label, returned
  `1`, explicitly left each filesystem unchanged, and made no repair.
- Complete direct reads covered every addressable device byte with no write:

| Label | Bytes read | Seconds | Result |
| --- | ---: | ---: | --- |
| `USB01_2G` | 2,013,265,920 | 197 | PASS, `dd` rc `0` |
| `USB05_4G` | 4,026,531,840 | 367 | PASS, `dd` rc `0` |
| `USB02_8G` | 8,053,063,680 | 518 | PASS, `dd` rc `0` |
| `USB03_32G` | 31,042,043,904 | 1,194 | PASS, `dd` rc `0` |

- The Pi kernel logged no USB reset, SCSI sense, medium, buffer-I/O, device
  offline, or block I/O error during the full reads.
- Final `sg_readcap` results matched the byte capacities above with 512-byte
  logical blocks.

## Disposition

All four specimens pass the non-destructive pretest health gate. Preserve the
Windows-created label-field condition unchanged because Windows-format
compatibility is part of the intended baseline. This evidence proves current
readability and filesystem consistency; it does not replace controller write,
publication, removal, or independent post-operation validation.
