dd
DestructiveBlock-level copy
dd if=<in> of=<out> bs=4M status=progress
Disk imaging and ISO writing. A wrong 'of=' destroys an entire disk — triple-check targets.
Examples
dd if=ubuntu.iso of=/dev/sdX bs=4M status=progressWrite ISO to USB
Syntax
dd if=SRC of=DST [bs=N] [count=N]
Before you run it
The of= target is irrevocably overwritten.
Check it once more before you run it
Some commands cannot be undone if one flag is wrong. An on-device reference works with no connection. Free to install, no ads.
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