A howto backup your software configuration. "installed-software".

[Tom H]

On Tue, Jun 5, 2012 at 12:28 PM, Bas Roufs - De. <basroufs at gmail.com> wrote:
>>
>> debconf-get-selections > selection.debconf
>
> On one hand, I do manage to generate the scrip "selection.debconf": via the
> command "sudo debconf-get-selections > selection.debconf".
>
>> debconf-set-selections < selection.debconf
>
> On the other hand, each attempt to use this script at another laptop with
> exactly the same OS ends up in various complications.
>
> For the time being, I keep using the other method along the lines of the
> instructions at this page: http://tinyurl.com/8yjrfpf

The debconf-... is in addition to your procedure, not a replacement of
it. It preserves the debconf settings.