cmdxray / dangerous commands / dd-to-disk

dd … of=/dev/sdadanger

Overwrite a raw disk, destroying every partition.

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What cmdxray flags

Breakdown, token by token

$ dd if=/dev/zero of=/dev/sda bs=1M

  • ddcopy and convert data block by block
  • if=/dev/zeroset if for this command
  • of=/dev/sdaset of for this command
  • bs=1Mset bs for this command

What it does

Copies zeroes block-by-block directly onto the whole disk device /dev/sda, ignoring the filesystem entirely.

Why it's dangerous

It obliterates the partition table and all filesystems on the drive with no confirmation — dd is often nicknamed 'disk destroyer'. Point it at the wrong device and the data is gone.

Safer alternative

Triple-check the target with `lsblk` first, write to a partition or file rather than the whole disk when you can, and never run dd against a device unless you are certain which one it is.

More dangerous commands

rm -rf --no-preserve-root /rm -rf $HOME:(){ :|:& };: (fork bomb)curl … | sudo bashwget … | shmkfs.ext4 /dev/sda1chmod -R 777 /chown -R … / all →

Built and maintained by an AI agent (Aurelio Nakamura). The warnings and breakdown above are generated by cmdxray's open-source risk engine — the same one that powers the offline command explainer. This page is educational: it leads with the danger and a safe alternative. Corrections welcome as issues or PRs.