how not to initialize HD

JB jb.123abc at yahoo.com
Sat Jul 31 23:36:29 UTC 2010


Darr <darr <at> core.com> writes:

> 
> I agree that 3 primaries don't need to be used before an extended partition 
> is created for logical volumes (I've done 1 primary and 1 extended before, 
> too), but why is there no /sda4 ?
> 
> i.e. If the extended partition was /sda2 would the first logical volume 
> *still* be /sda5? 
> 
Hi,
this is my system:
# cfdisk
                         cfdisk (util-linux-ng 2.17.2)

                              Disk Drive: /dev/sda
                        Size: 40007761920 bytes, 40.0 GB
              Heads: 255   Sectors per Track: 63   Cylinders: 4864

    Name        Flags	   Part Type  FS Type          [Label]        Size (MB)
 ------------------------------------------------------------------------------
    sda1        Boot        Primary   NTFS             [^B]            21436.05*
    sda2                    Primary   Linux ext3       [F13]            8388.61*
    sda3                    Primary   Linux ext3       [F11]		7605.21*
    sda5                    Logical   Linux swap / Solaris		1501.84*
    sda6                    Logical   Linux ext2       [save]		1076.07*
...

# fdisk -l
Disk /dev/sda: 40.0 GB, 40007761920 bytes
255 heads, 63 sectors/track, 4864 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x3db012b3

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1        2607    20933608+   7  HPFS/NTFS
/dev/sda2            2607        3626     8192000   83  Linux
/dev/sda3            3626        4551     7426960   83  Linux
/dev/sda4            4551        4864     2517480    5  Extended
/dev/sda5            4551        4734     1466608+  82  Linux swap / Solaris
/dev/sda6            4734        4864     1050808+  83  Linux

Note that fdisk shows Extended partition as sda4, but cfdisk skips it. It is
a matter of formatting the displays by both. The layouts were done by these
Linux utilities.

In case of Paul's layout there is some inconsistency, and that's why
I originally wanted to fill in the missing primary partitions.
I wonder if mixing various formatters (Windows, Linux's cfdisk, fdisk, gparted/
parted, etc) has any impact on that. I remember once using gparted and it
behaved differently from the cfdisk/fdisk utilities in regard to display and
reorganization of a layout. I am not able to answer this question
authoritatively.  
# fdisk -l

Disk /dev/sda: 100.0 GB, 100030242816 bytes
255 heads, 63 sectors/track, 12161 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xa8a8a8a8

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1        4462    35840983+   7  HPFS/NTFS
/dev/sda2            4463        4717     2048287+   e  W95 FAT16 (LBA)
/dev/sda3            4718       12162    59793409    5  Extended
Partition 3 does not end on cylinder boundary.
/dev/sda5            4718        5961     9989120   83  Linux
/dev/sda6            5962        8094    17133291   83  Linux
/dev/sda7           11919       12162     1951744   82  Linux swap / Solaris
/dev/sda8            8095       11918    30716248+   c  W95 FAT32 (LBA)

I am reading a web document about partitioning right now.
It is about Windows FDISK and  paragraph 5 is noteworthy:
Keep in mind that there are NO written rules and NO industry standards on how
FDISK should work but here are some basic rules that seem to be followed by most
versions of FDISK:
...
   5. The partition table entries (slots) can be used in any order. Some
versions of FDISK fill the table from the bottom up and some versions of FDISK
fill the table from the top down. Deleting a partition can leave an unused entry
(slot) in the middle of a table.
...

So, every OS will do it a little bit differently -:) .
JB




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