The dd command is a powerful tool for creating disk images on Mac OS X. Here’s how to use it:
- Open Terminal.
- Insert the source disk (e.g. a USB drive) that you want to create an image of.
- Run the following command to list the available disk devices:
diskutil list
- Identify the source disk by its size and partition information. For example, if the source disk is named
/dev/disk2, you would use the following command to create a disk image:
sudo dd if=/dev/disk2 of=~/Desktop/disk2.img
Note that the if option specifies the input file (the source disk), and the of option specifies the output file (the disk image). In this example, the disk image is saved to the Desktop with the name disk2.img.
- The
ddcommand will run for a while and will not display any output. To check the progress, you can use thekillcommand with theUSR1signal:
sudo kill -USR1 $(pgrep ^dd)
- When the
ddcommand has finished, you should have a disk image saved to your specified location. You can use this disk image to restore the source disk at a later time, or you can use it as a backup.
Note: Be careful when using the dd command, as it can overwrite the wrong disk if the input or output file is specified incorrectly. Always double-check your options and make sure you have a backup before using the dd command.