GNU utilities

Fill USB Flash with Zeroes on Linux

When formatting usb flash, it always only creates new partition table at the start sectors and remain all the rest as it was. So, it is possible to read the rest data, analyze and get old data if your flash will be in hacker's hands. If your data must be totally removed from flash, it needs to fill entire drive with zeroes.


Fill USB flash with zeroes with dd if=/dev/zero of=/dev/flash

Simplest way is to use 'dd', but it takes much time and reduces lifetime of usb flash:

dd if=/dev/zero of=/dev/FLASH