Network installation with custom repositories

[Vasily Makarov <einmalfel@gmail.com>]

Hi all!

I'm making a distribution based on debian-armhf and I need to make
this distribution to install over network on devices which are able to
boot kernel+initrd image over tftp. Installation process should take
packages from our public APT-repository + original debian repository
and from local mirrors of this repositories in case of failing
internet connection. After installation the devices will pull updates
from those repositories.

I'm new to packaging, so I'm looking for some advice.

Here is what I'm going to do:
- setup (with reprepro) public APT repository with our packages. The
packages of this repository belong to some component (lets name it C)
- add alternative apt package (with this repo added to sources.list)
to C component
- setup local mirrors of our own repo and of debian repo
- make kernel+initrd image with debian-installer available on local
network. Image will be preconfigured to take packages from internet
repositories and if this fails use local mirrors. Also packages from C
component are configured to have higher priority (as if they are
apt-pinned)

Is all this achievable (ideally via configuration only, not writing code)?
Are there more correct/simple ways of doing this?
Are there any common pitfalls with this approach?

Sorry, if this is not right mailing-list for this question,
Vasily.