/dev/sdb13 174706938 976768064 401030563+ fd Linux raid autodetect

The size of that partition is 802061126 sectors. From what i read - mdadm should have placed the actual superblock somewhere inbetween 128K and 64K to the very end. This is a raid0 array. The problem that i am facing is that i need to move the superblock on another partition/drive (sda13) which is currently shifted/spaced out (basically it shrunk and i need to expand it to the size of sdb13). I need to get the exact location/dimensions, a definite 1:1 (nothing extra or less). I have tried inspecting the partition in question with dd and xxd to inspect the start/end of the superblock - but it is somewhat misleading, i do not see any pattern of mdadm specific headers to be able to identify it. So far, i have only been able to locate the UUID (bytes are reversed: 7c6afc87 it stored as 87fc6a7c) - but still cannot make out either the end or the start of mdadm headers.

Perhaps someone can point me in the right direction?


Check out its version exactly: sudo mdadm -E /dev/sdb13

  • Version : 0.90.00 as i've already said – XXL Oct 9 '11 at 11:05
  • You didn't say that mdadm -E works fine and shows the info, actually. – poige Oct 9 '11 at 11:28
  • take a look at the thread's name. blatantly says "0.90", does it not? also, what do you mean by "mdadm -E works fine and shows the info, actually" - i never said it did not, huh? btw, it only shows the superblock offsets for 1.2 – XXL Oct 9 '11 at 11:30
  • mdadm -E also should indicate offset of data and superblock in sectors. – poige Oct 9 '11 at 11:32
  • for 1.2, not 0.90 – XXL Oct 9 '11 at 11:32

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