Howto mix releases

If you want to install some packages from testing without upgrading your whole stable system to testing you can tell apt how to deal with different releases:

add testing and/or unstable repos to your sources.list
edit apt.conf
edit preferences
apt-get install […]

Recommended reading:

http://www.debian.org/doc/manuals/apt-howto/index.en.html
man 5 apt_preferences

/etc/apt/apt.conf

APT::Default-Release "stable";

/etc/apt/preferences

Package: *
Pin: release a=stable
Pin-Priority: 900

Package: *
Pin: release a=testing
Pin-Priority: 90

What the pin priorities mean: http://www.debian.org/doc/manuals/apt-howto/ch-apt-get.en.html#s-pin

Tools

apt-cache policy foo
apt-show-versions

Howto invoke apt-get

apt-get install foo/testing
apt-get install foo=1.0-1
apt-get install –target-release testing foo

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