location of the "disk identifier" According to Wikipedia, "disk signature" is a 32 bit value stored in MBR on bytes 440 - 443. According to `fdisk`, my "disk identifier" is _00043afc_ in hex: # fdisk -lu /dev/sda | grep identi Disk identifier: 0x00043afc # However, I can not confirm this with `dd`: # dd if=/dev/sda skip=439 bs=1 count=4 2>/dev/null | xxd -ps c3fc3a04 # Even if I check the entire MBR, I do not see the "disk identifier": # dd if=/dev/sda bs=512 count=1 2>/dev/null | xxd -ps | grep 43a # Where is the "disk identifier" stored?

It appears that you found your answer with the first `dd` already. It's just in different endian order. Read the bytes (two-character hex sequences) reverse. And set the skip value to 440 instead of 439.