first block in ext3 filesystem

Mulyadi Santosa mulyadi.santosa at gmail.com
Tue Aug 7 02:03:31 EDT 2012


Hi...

On Tue, Aug 7, 2012 at 1:04 AM, Prashant Shah <pshah.mumbai at gmail.com> wrote:
> Hi,
>
> I came across this
>
> $sudo dumpe2fs /dev/sda1
>
> 4KB Block Size
> Group 0: (Blocks 0-32767)
>   Primary superblock at 0, Group descriptors at 1-1
>
> 1KB Block Size
> Group 0: (Blocks 1-8192)
>   Primary superblock at 1, Group descriptors at 2-2

I think it has something to do with the alignment. At the first case,
your 4K block size formatted partition align perfectly, so it is
usable right from block 0.

OTOH, on 1K block size, block 0 must be skipped and starting from
block 1, it align perfectly.

Not sure which alignment size your disk use. Maybe it's 4K, since
nowadays 4K disk is becoming common ones

CMIIW people...

-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com



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