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Re: Formatting a 32G or 16G SD card?

On Thu, Jan 03, 2019 at 12:07:21AM -0800, John Conover wrote:
I'm want to format a "standard" 16G/32G SD card to OEM format.

Could someone please verify that the following will do this:

   mkdosfs -I /dev/sdX
   fdisk /dev/sdX n,p,1,default,default,w
   mkfs.vfat /dev/sdX1

It seems to work, but could someone please verify that its correct?

The "mkdosfs" seems to be superfluous, to me. As far as I can see, that
will put a FAT16 filesystem directly onto the device. You then write a
MBR-type filesystem over the top of it, and then a FAT32 filesystem into
the sole partition.

That said the documentation for mkdosfs "-I" is pretty unclear so
perhaps it's doing something that you intend and I have missed.

I assume  the arguments to fdisk are intended to indicate the
interactive options you would supply when running it and are not
explicitly command-line arguments. I think fdisk will suggest an offset
for the partition that is a multiple of the physical block size already,
which you probably want.


⣾⠁⢠⠒⠀⣿⡁ Jonathan Dowland
⢿⡄⠘⠷⠚⠋⠀ https://jmtd.net
⠈⠳⣄⠀⠀⠀⠀ Please do not CC me, I am subscribed to the list.