Re: [gentoo-user] Creating an firmware image from a too large microSDcard...?

J. Roeleveld <joost@××××××××.org> [16-01-16 07:24]:
> On 16 January 2016 04:50:49 CET, Meino.Cramer@×××.de wrote:
> >Hi,
> >
> >to post a firmware image of my embedded linux computer
> >to a friend I want to size it down.
> >
> >System wise I did that already (only the really necessary
> >stuff of Gentoo plus some configuration and addons related
> >to the embedded system)...the problem comes with the size of
> >the microSDcard I use: 32 GB....
> >
> >The microSDcard (source) has two partitions (boot + the rest).
> >The boot partition is the first partition and it is of a fixed
> >and tiny size. The second partition contains the "rest": Gentoo.
> >Currently the used space of this partition is also small.
> >
> >The image needs to be of a format, which makes
> >it possble to 'dd' it onto a microSDcard (target) and afterwards use
> >g/parted to resize/expand the second partition to the end
> >of the microSDcard to get all storage space available.
> >
> >If I dd the source into an image I get all those zeroes also and
> >the image only will fit onto a microSDcard (target) of at least
> >the same size.
> >
> >If I dd each partition separately I get two files and the partition
> >table is not copied...may be technically possible but not user
> >friendly.
> >
> >How can I manage to get an image from my microSDcard (source), which
> >only consists of the used space in a way that it can be put onto
> >another microSDcard (target) in the waay described above?
> >
> >How can I acchieve that magic ?  ;) :)
> >
> >Thank you very much in advance for any help!
> >Best regards,
> >Meino
>
> I would create a script that partitions and formats the sdcard.
> Then untar the contents of the partitions
> Then set up the bootloader.
>
> This should lead to a small size which is also user friendly.
>
> --
> Joost
> --
> Sent from my Android device with K-9 Mail. Please excuse my brevity.
>

Hi Joost,

thanks for your help.

Due to technical circumstances I am urged to use the "dd-way" to 
create the contents.

How can I accomplish, what I have described?

Thank you very much in advance for any help ! :)

Best regards,
Meino