Hands-on 07-smart-disk-health-and-failure-warning: Lab

name

Classify synthetic SATA and NVMe health reports

scope

All files created or changed by this lab are confined to /opt/lab-classroom/class76/. The reports are synthetic teaching fixtures and are not measurements from the student's hardware.

steps

step

1

instruction

Confirm that the pre-provisioned lab directory exists and is writable. This check is read-only.

command

test -d /opt/lab-classroom/class76 && test -w /opt/lab-classroom/class76 && printf '%s\n' 'class76 directory is ready'

step

2

instruction

Create two explicitly labeled synthetic health reports.

command

python3 - <<'PY'
from pathlib import Path
root = Path('/opt/lab-classroom/class76')
if not root.is_dir():
raise SystemExit('Required lab directory does not exist')
(root / 'synthetic-sata.txt').write_text('''SYNTHETIC TRAINING DATA
Device Model: Academy SATA Example
SMART overall-health self-assessment test result: PASSED
ID# ATTRIBUTE_NAME VALUE WORST THRESH RAW_VALUE
5 Reallocated_Sector_Ct 100 100 010 0
194 Temperature_Celsius 066 055 000 34
197 Current_Pending_Sector 100 100 000 12
198 Offline_Uncorrectable 100 100 000 3
199 UDMA_CRC_Error_Count 200 199 000 41
''', encoding='utf-8')
(root / 'synthetic-nvme.txt').write_text('''SYNTHETIC TRAINING DATA
Model Number: Academy NVMe Example
Critical Warning: 0x00
Temperature: 39 Celsius
Available Spare: 100%
Available Spare Threshold: 10%
Percentage Used: 7%
Unsafe Shutdowns: 2
Media and Data Integrity Errors: 4
Error Information Log Entries: 4
''', encoding='utf-8')
print('Synthetic fixtures created')
PY

step

3

instruction

Create a small classifier that demonstrates why overall health and Critical Warning fields must not be evaluated alone.

command

python3 - <<'PY'
from pathlib import Path
root = Path('/opt/lab-classroom/class76')
program = '''from pathlib import Path
import re

ROOT = Path("/opt/lab-classroom/class76")

def sata_value(text, name):
match = re.search(r"^\s*\d+\s+" + re.escape(name) + r"\s+\d+\s+\d+\s+\d+\s+(\d+)", text, re.MULTILINE)
return int(match.group(1)) if match else None

def named_number(text, label):
match = re.search(r"^" + re.escape(label) + r":\s+(\d+)", text, re.MULTILINE)
return int(match.group(1)) if match else None

sata = (ROOT / "synthetic-sata.txt").read_text(encoding="utf-8")
nvme = (ROOT / "synthetic-nvme.txt").read_text(encoding="utf-8")

pending = sata_value(sata, "Current_Pending_Sector")
uncorrectable = sata_value(sata, "Offline_Uncorrectable")
crc = sata_value(sata, "UDMA_CRC_Error_Count")
media_errors = named_number(nvme, "Media and Data Integrity Errors")
critical_warning = re.search(r"^Critical Warning:\s+(0x[0-9a-fA-F]+)", nvme, re.MULTILINE)
critical_warning = critical_warning.group(1) if critical_warning else "missing"

print("SATA overall field: PASSED")
print(f"CRITICAL: SATA pending sectors={pending}; preserve evidence, verify recovery, and plan replacement.")
print(f"CRITICAL: SATA offline uncorrectable sectors={uncorrectable}; data could not be corrected.")
print(f"WARNING: SATA CRC error count={crc}; establish a baseline and inspect the transport path if it grows.")
print(f"NVMe Critical Warning field: {critical_warning}")
print(f"CRITICAL: NVMe media and data integrity errors={media_errors}; a zero Critical Warning field does not cancel this evidence.")
'''
(root / 'classify_health.py').write_text(program, encoding='utf-8')
print('Classifier created')
PY

step

4

instruction

Run the classifier without creating bytecode files.

command

PYTHONDONTWRITEBYTECODE=1 python3 /opt/lab-classroom/class76/classify_health.py

step

5

instruction

Review the synthetic evidence manually and compare it with the classifier output.

command

grep -E 'PASSED|Pending|Uncorrectable|CRC|Critical Warning|Percentage Used|Media and Data' /opt/lab-classroom/class76/synthetic-sata.txt /opt/lab-classroom/class76/synthetic-nvme.txt

step

6

instruction

Write a response note that stays inside the lab directory and records an appropriate operational decision.

command

operational_extension

After the lab, an administrator may inspect real devices using approved read-only collection procedures. Device access, controller pass-through options, self-tests, and replacement operations must follow the host or storage-platform runbook and are intentionally excluded from this low-risk lab.