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ReclaimNUKM Wipe Methods Documentation

NUKM Definition: NUKM is defined by the acronym for 'Next Unit of Kill Module' as it pertains to data sanitization.

Overview

ReclaimNUKM provides three different data sanitization methods for securely wiping storage devices. Each method offers different levels of security, speed, and compliance with data destruction standards.

NEW in v1.5: Hardware error compensation with ddrescue support, USB NVMe enclosure handling, and multiple filesystem formatting options.

Supported Drive Types

Standard Drives

SATA HDD/SSD (512B/4KB sectors)
NVMe drives (512B/4KB sectors)
Standard consumer and commercial drives

Enterprise Drives (v1.4+)

SCSI/SAS drives with proprietary sectors
NetApp, Toshiba, and other enterprise storage
Drives with 520B/528B sector sizes
Drives with protection types and data integrity features

USB NVMe Enclosures (v1.5+)

USB NVMe enclosures (RTL9210, RTL9220, JMicron, ASMedia)
External NVMe drive enclosures
Drives requiring special initialization procedures

Wipe Methods

1. Quick Format

Purpose: Fast sanitization with partition creation and filesystem formatting.

What it does:

Creates a new partition table (GPT for drives >2TB, MSDOS otherwise)
Creates a single primary partition using the entire drive
Formats the partition with the selected filesystem (exFAT, NTFS, EXT4, or none)
Applies appropriate volume labels using centralized label generation
Updates partition information and settles udev

Filesystem Options:

exFAT Quick: Fast formatting with exFAT filesystem
exFAT Full: Full formatting with exFAT filesystem (slower but more thorough)
NTFS Quick: Fast formatting with NTFS filesystem
NTFS Full: Full formatting with NTFS filesystem using mkfs.ntfs -f
EXT4 Quick: Fast formatting with EXT4 filesystem using -F flag
EXT4 Full: Full formatting with EXT4 filesystem using -cc flag
Format Options: None: Skip formatting (partitioning only)

Use cases:

Preparing drives for immediate use with specific filesystems
Creating bootable drives with Windows/Linux compatibility
Quick preparation of drives for new deployment
When both wiping and formatting are needed

2. DD Zero Fill

Purpose: Complete single-pass overwrite sanitization with hardware error compensation.

What it does:

Uses either dd or ddrescue to write zeros across the entire drive
Overwrites every sector with binary zeros
Provides complete data destruction through overwriting
NEW: Hardware error compensation mode using ddrescue for error-resilient operations

Standard Mode (dd):

Uses standard dd command with progress tracking
Fails on the first bad sector encountered
Suitable for healthy drives

Hardware Error Compensation Mode (ddrescue):

Uses ddrescue with error mapping and recovery
Continues operation despite bad sectors
Creates mapfile for resumable operations
Automatically handles hardware errors and bad sectors

Use cases:

General-purpose data destruction
Preparing drives for secure disposal
Wiping drives with potential bad sectors
When hardware errors should not stop the wipe process

3. Shred

Purpose: Multi-pass secure deletion following Department of Defense standards.

What it does:

Performs 3 random data passes over the entire drive
Uses cryptographically secure random data from /dev/urandom
Follows with a final zero-fill pass
Uses GNU shred with verbose output and progress tracking

Use cases:

High-security data destruction
Compliance with government standards
Maximum assurance of data irrecoverability
Military or classified data handling

USB NVMe Enclosure Support

Automatic Detection:

Identifies USB NVMe enclosures by vendor/model information
Detects RTL9210, RTL9220, JMicron, ASMedia chipsets
Shows warnings for drives requiring special handling

Initialization Procedures:

Multiple wake-up attempts for problematic enclosures
I/O operations to initialize zero-capacity drives
SCSI start/stop unit commands
USB device reset using usbreset utility
Power cycling via UDisks

Recovery Methods:

Metadata clearing for drives showing zero size
Partition table recreation with fdisk
GPT creation with parted
Additional I/O wake-up sequences

Comparison Table

Method	Security Level	Speed	Compliance Standards	Data Recovery Risk
Quick Format	Basic-Medium	⚡ Fastest	None	Medium (filesystem recreation possible)
DD Zero Fill	High	🟡 Medium	Basic overwrite standards	Low (requires advanced forensics)
DD Zero Fill (HW Comp)	High	🟡 Medium-Slow	Basic overwrite standards	Very Low (handles bad sectors)
Shred	Maximum	🐌 Slowest	DoD 5220.22-M (3-pass)	Very Low (extremely difficult)

Sanitization Standards Compliance

Quick Format

No formal compliance: Provides basic data removal through partitioning and formatting
Risk level: Medium - Data can be recovered with forensic tools, but filesystem is destroyed
Benefits: Fast, creates usable drive with selected filesystem

DD Zero Fill (Standard)

Basic overwrite compliance: Meets simple single-pass overwrite requirements
Standards: Aligns with basic data destruction guidelines but not comprehensive standards
Risk level: Low to medium - Single pass overwrite makes recovery difficult but not impossible

DD Zero Fill (Hardware Error Compensation)

Enhanced overwrite compliance: Meets single-pass requirements with error handling
Standards: Aligns with data destruction guidelines for drives with bad sectors
Risk level: Very low - Error compensation ensures complete coverage despite hardware issues

Shred (3-pass + zero)

DoD 5220.22-M compliance: Meets U.S. Department of Defense data sanitization standard
NIST SP 800-88 Guidelines: Aligns with National Institute of Standards and Technology recommendations
Risk level: Very low - Multiple random passes make data recovery extremely difficult and expensive

Performance Characteristics

Speed Rankings (Fastest to Slowest)

Quick Format - Minutes (depends on drive size and filesystem, typically 5-30 minutes)
DD Zero Fill (Standard) - Hours (full drive write time, e.g., 2-8 hours for 1TB drive)
DD Zero Fill (HW Comp) - Hours-Slow (ddrescue overhead, e.g., 3-10 hours for 1TB drive)
Shred - Days (3 full passes + zero pass, e.g., 6-24+ hours for 1TB drive)

Factors Affecting Speed

Drive size and interface (SSD vs HDD)
Drive write speed and health
Filesystem selection for Quick Format
Hardware errors (affects ddrescue performance)
System performance and background load

Security Considerations

When to Use Each Method

Choose Quick Format when:

Speed is critical and some security is acceptable
Drive will be immediately reformatted and reused
Specific filesystem formatting is required
Creating drives for OS installation or immediate use

Choose DD Zero Fill (Standard) when:

Balance of speed and security is needed
Drive is known to be healthy
Single overwrite is acceptable
Preparing drives for donation or disposal

Choose DD Zero Fill (HW Error Comp) when:

Drive may have bad sectors or hardware issues
Maximum coverage is required despite errors
Resumable operations are needed
Working with aging or damaged drives

Choose Shred when:

Maximum security is required
Compliance with government standards is needed
Data contains sensitive or classified information
Legal or regulatory requirements demand high assurance

Data Recovery Feasibility

Quick Format: Medium feasibility - forensic tools can recover data, but filesystem is destroyed
DD Zero Fill: Low feasibility - requires expensive forensic equipment
DD Zero Fill (HW Comp): Very low feasibility - ensures complete coverage
Shred: Very low feasibility - economically impractical to recover

Technical Implementation

Command Execution

All methods are executed via bash scripts with:

Comprehensive logging with timestamps
Progress monitoring and status updates
Error handling with retry mechanisms
Sudo privilege escalation
Terminal output streaming

Logging and Verification

Each operation creates detailed log files
Timestamps and duration tracking
Master log aggregation
Verification of successful completion
Hardware health reporting (SMART data)

Filesystem-Specific Handling

exFAT: Uses mkfs.exfat with volume labels
NTFS: Uses mkfs.ntfs with -f (fast) or default (full) options
EXT4: Uses mkfs.ext4 with -F (fast) or -cc (full) options
Volume Labels: Centralized generation ensuring consistency across filesystems

Best Practices

Verify drive selection before starting any wipe operation
Ensure no critical data remains on the system
Monitor progress especially for long-running operations
Keep logs for compliance and audit purposes
Test on small drives first if unsure of the process
Enable hardware error compensation for drives with potential issues
Check USB NVMe enclosures for proper initialization

Troubleshooting

Common Issues

Slow performance: Check drive health and connection, consider hardware error compensation
Permission errors: Verify sudo configuration includes all required commands
Device not found: Refresh device list or check connections, try USB port changes for NVMe enclosures
Filesystem creation fails: Check that required tools are installed (mkfs.exfat, mkfs.ntfs, mkfs.ext4)
USB NVMe issues: Try different USB ports, check kernel logs, ensure proper initialization

Recovery Options

Stopped operations can be resumed (ddrescue supports mapfiles)
Failed operations are logged with error details
Device status is tracked to prevent accidental re-wiping
Hardware error compensation allows continuation despite bad sectors

⚠️ WARNING: This documentation is for ReclaimNUKM version 1.6.0 with GUI interface. Always ensure you have proper backups before performing any data destruction operations.