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what_is_an_mbr [2018/04/19 07:41]
gurce
what_is_an_mbr [2018/04/19 22:02] (current)
– [What is an MBR?] gurce
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 Now, the reason why I referred to the MBR before as being 'optional' was due to the following case. Now, the reason why I referred to the MBR before as being 'optional' was due to the following case.
  
-What it if we just want a single partition to expand the entire disk's contents. Well, there are two ways of specifying this:+What it if we just want a single partition to span the entire disk's contents. Well, there are two ways of specifying this:
  
-  * Have an MBR that specifies just a single partition that spans the entire disk+  * Have an MBR that specifies just a single partition that spans the entire disk (apart from the first 512 bytes needed for the MBR)
   * Omit the MBR, and just let the single partition span the entire disk (including the first 512 bytes where the MBR would have been)   * Omit the MBR, and just let the single partition span the entire disk (including the first 512 bytes where the MBR would have been)
  
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 ====== How can I tell if my USB stick has an MBR or not ====== ====== How can I tell if my USB stick has an MBR or not ======
  
-Being a techy guy, I tend to figure this out by using linux tools like dd and hexdump, to assess the first bytes of the drive, with a line such as this:+Being a techy guy, I tend to figure this out by using linux tools like dd and hexdump, to assess the first 512 bytes of the drive, with a line such as this:
  
 ''dd if=/dev/disk2 bs=1 count=512 2> /dev/null | hexdump -C -v | less'' ''dd if=/dev/disk2 bs=1 count=512 2> /dev/null | hexdump -C -v | less''
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 Doing things this way is probably not to everybody's liking though, so if I learn of easier ways of ascertaining this, I will jot them down for you here. Doing things this way is probably not to everybody's liking though, so if I learn of easier ways of ascertaining this, I will jot them down for you here.
 +
 +====== How do I format without an MBR, so that I can replicate this issue ======
 +
 +For testers that want to replicate this issue on their USB sticks, you can format it from linux with a command such as this:
 +
 +''mkfs.msdos -I /dev/sdX'' (replacing X with the drive letter of your usb stick)
what_is_an_mbr.1524145288.txt.gz · Last modified: 2018/04/19 07:41 by gurce