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I managed to UDF format my USB drive following the instructions in Using UDF on a USB flash drive. Later, I came by this post and I began to doubt...

Could anyone explain which would be the "best" way of UDF formatting a USB drive taking into account both the question and the link provided? (I'm assuming that the link is trustworthy, but could be mistaken.)

Additionally: the linked question talks about zeroing the first sectors of the USB drive, I usually just go:

cp /dev/zero > /dev/sdX

and Ctrl+C my way out of it... does anyone know exactly how many bytes should be zeroed? (a snippet would be nice too :) )

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up vote 2 down vote accepted

You should zero at least 2048 bytes because UDF needs the first 2K area.

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To be more precise: this first zone WILL NOT be erased by UDF. (This zone is intentionnally left as-is, so it can be used to store, e.g.: bootloaders. Like on bootable DVDs. And UDF-as-a-USB-stick-format also use this zone for a special partition table) If you format a USB stick with mkudffs, whatever was in those 2048 bytes will still be around to confuse your OS. If there was a FAT32 partition there instead, there will still be enough of it left in the "bootloader area" of UDF so an OS might see it, and think that this is a FAT32 partition. – DrYak Mar 23 at 15:13

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