**Secure Data Erasure Script (Bash)** This Bash script securely erases data from a specified device with random data, ensuring irrecoverability. Use with caution.

secure_erase.sh

#!/bin/bash

# Check if the script is run with superuser privileges
if [ "$EUID" -ne 0 ]; then
  echo "Please run this script as root (sudo)."
  exit 1
fi

# Prompt the user for the target devices
read -p "Enter the target devices (e.g., /dev/sdX /dev/sdY): " target_devices

# Iterate through the space-separated list of target devices
for device in $target_devices; do
  # Check if the device exists
  if [ ! -e "$device" ]; then
    echo "Device $device does not exist."
    continue
  fi

  # Overwrite with random data
  echo "Erasing $device..."
  dd if=/dev/urandom of="$device" bs=4M status=progress
  echo "Finished erasing $device."
done

Good job!

Great, this is very useful 👍

What is that bs=4M in line 22?

What is that bs=4M in line 22?

bs specifies how much bytes should be read and written from/to the device at a time (can be set separately by ibs and obs! bs override those).
You can check the man page of dd(1) or via man7.org
dd(1) deals with a device at byte level and therefore accessing with bigger chunk size, speeds up the process but also takes more RAM!

it would be a good idea to use /dev/random since it has more entropy, the disadvantage being if there is not enough entropy you will have to wait

also this command if you are really paranoid about it
openssl enc -aes-256-ctr -pass pass:"$(dd if=/dev/urandom bs=128 count=1 2>/dev/null | base64)" -nosalt < /dev/zero > /dev/sdx

it would be a good idea to use /dev/random since it has more entropy, the disadvantage being if there is not enough entropy you will have to wait

IMO, it doesn't matter if data is random or not, I would've use all zeros...

did you ever heard of dban or shredos?

I didn't know them, thanks