shred wipe all data in ubuntu

sudo shred -vfz /dev/sdX

1. -n , --iterations=N. Instead of the default (3) times, overwrite the data N times.
2. -z , --zero. Add a final overwrite with zeros to hide shredding.
3. -f , --force. Force the permissions to allow writing if necessary.
4. -v , --verbose. Show progress in detail.
5. -u , --remove. Truncate and remove file after overwriting.