Setting up a mixed Debian system

As the vast majority of Debian already knows, it has several branches:

• Stable
• Testing
• Unstable (Sid)

But there is also a possibility to make a mixed system by making mixtures like:

• unstable + experimental
• stable + testing
• stable + unstable
• stable + testing + unstable

Let's see how to do it

First of all, for safety we must make a copy of our sources.list, for this we enter the file:

nano /etc/apt/sources.list

When we have done this we add the repositories of the branch or branches that we want in the sources.list, for example

now we save the file and execute:

apt-get update

Now we will prepare two files: preferences and apt.conf

nano /etc/apt/preferences

In this file we add the following:

NOTE: This is an example, everything will depend on the repositories that we want to put

We create apt.conf:

nano /etc/apt/apt.conf

We add the following:

APT::Default-Release "testing";
APT::Cache-Limit 15000000;
Apt::Get::Purge;
APT::Clean-Installed;
APT::Get::Fix-Broken;
APT::Get::Fix-Missing;
APT::Get::Show-Upgraded "true";

We update the database:

apt-get update

And now we have two options to install packages:

The typical and the following:

apt-get install -t version_de_debian nombre_paquete

This way of installing will install the desired package for the specified version, resolving dependencies automatically.

Source: It's Debian