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Humber
Asked: 2010-01-06 04:41:51 +0800 CST

Check bootloader existence in a block device

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How can I check if a bootloader (i.e. grub2) is installed on a block device (e.g. CF card)? I know I can mount the device and peek some files but how can I be sure the bootloader is installed without having to test it (try to boot it on some device) Thanks in advance

linux

1 Answers

  1. Best Answer

    This can be achieved quite easily by using the dd(1) command and copying the first 512 bytes from a given medium. Like:

    dd if=/dev/sdX of=mbr-sdX bs=512 count=1

    Then check if that file contains the hex signature ``0xAA55'' (don't forget to account for endianess of the machine). See [1] for more details.

    [1]http://mirror.href.com/thestarman/asm/mbr/GRUB.htm

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