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Accepted
Mon Villalon
Asked: 2011-08-18 20:13:13 +0800 CST

Disk block size reported as 1

  • 772

When i run 

cat /proc/partitions

I get ( notice the block size of sd4 )

major minor  #blocks  name

   8     0 1169686528 sda
   8     1     104391 sda1
   8     2    2096482 sda2
   8     3    2096482 sda3
   8     4          1 sda4
   8     5 1165387198 sda5

but if I run 

/sbin/fdisk -l /dev/sda

I get again ( notice sda4 )

Disk /dev/sda: 1197.7 GB, 1197759004672 bytes
255 heads, 63 sectors/track, 145619 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          13      104391   83  Linux
/dev/sda2              14         274     2096482+  83  Linux
/dev/sda3             275         535     2096482+  82  Linux swap / Solaris
/dev/sda4             536      145619  1165387230    5  Extended
/dev/sda5             536      145619  1165387198+  83  Linux

This may have something to do with the servers raid configuration as the sda4 is not even mounted or in fstab.

Is this normal?

hard-drive linux raid

2 Answers

  1. Best Answer

    /dev/sda4 is showing as having no useful size because it is, in effect, "not a partition". It's an "extended" partition, that is, a container for other partitions. In short, it is a strange and annoying artifact of the limitations of the DOS format partition table. You can ignore it for the purposes of answering the question "what partitions do I have?"

    For a ridiculous amount of information on the format and it's history, consult Wikipedia.

    • 1

  2. look at the start and end cylinders on sda4 and sda5, i think something happened with fdisk and sda5 has overwritten sda4.

    Try partitioning sda4 and sda5 again

    • -1