Creating bootable USB on a Mac

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djdawson

New member
Apr 19, 2024
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I just wanted to share my experience of successfully creating a bootable Spinrite 6.1 USB stick on my Mac (the last of the Intel 16" MacBook Pro laptops running the latest Sonoma 14.4.1 macOS). There's really nothing special about the process if you've ever done a similar thing to create a bootable device, such as a "pfSense" boot image, since it's the same process described in many places on the web using the "dd" command in the Terminal app. I used the process as described in this Centos support page, but it's also shown in this short YouTube video (though I used the "/dev/rdisk2" device instead of the "/dev/disk2" device shown in the video for the "of=" parameter, since "r" devices are a bit faster, but for this small Spinrite image that shouldn't really matter). I happened to use an old 8 GByte Sandisk USB3 stick I had sitting around, but I don't think that's important. The "sr61.img" file in the "sr61.zip" download file worked perfectly, and is currently running on my wife's very old Asus laptop. Here's the exact command I used after unmounting the USB drive (which was /dev/disk2 on my system but you should be extremely careful to verify that you're specifying the correct device for your USB stick):

Code:
sudo dd if=sr61.img of=/dev/rdisk2 bs=1m status=progress
 
@djdawson : Thanks for sharing the approach you took. I agree that using the built-in native “dd” command is THE best/right way for a power user to tackle moving an .IMG file to a USB device. And I also agree with your admonishment:
but you should be extremely careful to verify that you're specifying the correct device for your USB stick
For that reason, another Mac user pointed to a VERY slick, minimal and fool proof solution. It's some open source freeware called balenaEtcher at: https://etcher.balena.io/#download-etcher. It's large (452MB installed) for what it does, but it can be uninstalled after it does its job. And its HUGE benefit is that it's just impossible to get wrong. (y) Thanks again for sharing your “correct” way of doing this!
 
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