dd
Table of Contents
1. Usage
Create a file of arbitrary size
dd if=/dev/random of=/var/tmp/file1.db count=100 bs=1M # 100MB db dd if=/dev/zero of=/tmp/mytempimage.img count=500 bs=1M # 500MB img
How fast disk IO is happening
dd if=/dev/zero of=speedtest bs=1G count=50 conv=fdatasync
2. Resources
- https://www.reddit.com/r/commandline/comments/hckwrq/explain_dd_command_to_me/
- https://www.reddit.com/r/linuxquestions/comments/rm8fqt/help_with_understanding_how_to_use_the_dd_command/
- https://unix.stackexchange.com/questions/189030/why-specify-block-size-when-copying-devices-of-a-finite-size/189091#189091
- https://www.pixelbeat.org/docs/coreutils-gotchas.html
- https://www.reddit.com/r/linuxquestions/comments/r7zmll/dd_for_beginners/
- https://www.reddit.com/r/linux/comments/dkce3/how_and_when_to_use_the_dd_command/
- https://www.reddit.com/r/linuxquestions/comments/qo90ca/how_does_dd_work/
- https://www.reddit.com/r/ManjaroLinux/comments/o62s17/understanding_dd_command/
- https://www.reddit.com/r/linuxmasterrace/comments/82alc1/eli5_dd_command_options/
- https://www.reddit.com/r/learnprogramming/comments/2x8s2q/question_about_the_dd_unixlinuxqnx_command/
- https://www.reddit.com/r/raspberry_pi/comments/xkx990/how_to_use_count_parameter_in_dd_command_properly/
- https://www.reddit.com/r/linux/comments/62clm6/why_use_dd_for_writing_disk_images_to_devices/
3. Others
ddwas originally to be calledccfor "character copy", but because cc was already taken by the C compiler, the next letter in the alphabet was taken.