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Date: Mon, 15 Jul 2019 10:15:52 +0100
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To: sparvu@kronometrix.org, freebsd-arm@freebsd.org
Subject: Re: recreate FreeBSD 12 ARM image
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Stefan Parvu <sparvu@kronometrix.org> wrote:

> Suppose I have installed FreeBSD 12 on a 32GB microSD under RBPI3B+ and I have
> configure it as I want, add my own software and now I want to re-create the image as 
> small as possible say as the original. Is it possible to do something like this ? Anyone
> any advices, tips how can you do this ? 

Do you mean make a snapshot copy of the card so you can distribute it elsewhere,
but with the copy of the (largely empty) disk not using the full 32GB?

I.E. Stick the card into another system, don't mount it, but do:

dd if=/dev/DEVICE-NAME bs=1m | gzip -c > img.gz

This will copy the disk image, and compress it with gzip before saving it
to the file.