UFS Installing a new operating system using DD


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I've tried using FreeBSD but due to a lot of unsupported software and a few strange interactions with my CPU I simply wish to install another operating system. On Linux this would be easy, just use 'dd if=myiso.iso of=/dev/sdb (my ssd partition)'. However, when I tried to do this on FreeBSD, I got an 'operation not permitted' error.

I attempted to run it using this command: 'dd if=/root/Downloads/myiso.iso of=/dev/ada1', where I used ada1 assuming it was my SSD.

How can I achieve what I'm trying to do on FreeBSD? Yes I understand that using a USB is the easiest option but it was a perfectly viable option on Linux, and I don't see why that would change on FreeBSD.


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FreeBSD protects the boot sector of the boot disk against accidental overwriting. It simply prevents you from shooting yourself in the foot.

sysctl kern.geom.debugflags=16



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With dd(1) you're transfering all data of the source device, including metadata describing the filesystem. Usually, on an .iso there's an ISO-9660 filesystem, whereas on a HDD/SSD other filesystems are expected. For FreeBSD these are usually UFS & ZFS. Thus, if you want to "transfer" an OS from an ISO image to your HDD/SSD, use the installer. It does some more tasks than just copying files.