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

[Neil Bothwick]

On 16 January 2016 12:27:15 GMT+00:00, Meino.Cramer@×××.de wrote:
> Neil Bothwick <neil@××××××××××.uk> [16-01-16 13:23]:
> > On Sat, 16 Jan 2016 13:02:04 +0100, Meino.Cramer@×××.de wrote:
> >
> > > You dd the image on a sdcard, put that one in a reader, copy two
> files
> > > from /boot to /media/boot, put the sdcard into the OrangePI-PC,
> boot
> > > it, log in via ssh and call a script named "fs_resize", the miniPC
> > > reboots...and VOILA!
> > >
> > > Now I want to create such an image from parts of another image
> > > (kernel, firmware) and a bootable Gentoo minimal setup.
> > >
> > > For that I need to understand the trick which is used to create
> such
> > > images.
> >
> > Raspbian images do a similar thing, with an option in raspi_config
> to
> > resize the root filesystem to fill the card. There's no real trick,
> just
> > create the system you want on the smallest SD card that will hold
> it,
> > include the resize script and dd that card to an image.
> >
> >
> > --
> > Neil Bothwick
> >
> > Copper wire was invented by two Scotsmen fighting over a penny!
>
> My problem is, that I dont know which will be the final size of
> that image. So I will take a sdcard, which is big enough in
> any case.....and end up with the problem, which caused my first
> posting of this thread....;)
> And I am not owning a great variety of sdcards...especially when
> it comes to feature of being EMPTY sdcards...;)
>
> Best regards,
> Meino

Set it up on your 32GB card then, when you know how much space it uses, rsync it to a suitable card, like I said previously. You'll need a smaller card anyway, to test that it works, and microSD cards are really cheap now. 
-- 
Sent from my Android phone with K-9 Mail. Please excuse my brevity.