Fichier préferences

est il indipensable d’ajouter un fichier dans preferences pour autoriser les mises a jour automatique des paquets “backports”.

backports.debian.org/Instructions/#index3h2

À demi automatique. Les paquets déjà installés seront automatiquement proposés à la mise à jour. Il faudra toutefois volontairement les installer la première fois.
En se contentant des dépôts stable+backports, le fichier preferences ne devrait pas être nécessaire.

À signaler , backports désormais intégré aux dépôts réguliers.
backports.debian.org/news/Backpo … n_archive/

[code]
Dear users of the backports service!

The Backports Team is pleased to announce the next important step
on getting backports more integrated. People who are reading
debian-infrastructure-announce[1] will have seen that there was an
archive maintenance last weekend: starting with wheezy-backports the
packages will be accessible from the regular pool instead of a separate
one.

== For Users ==

What exactly does that mean for you? For users of wheezy, the
sources.list entry will be different, a simple substitute of squeeze
for wheezy won’t work. The new format is:

deb http://ftp.debian.org/debian/ wheezy-backports main

So it is debian instead of debian-backports, and offered through the
regular mirror network. Feel invited to check your regular mirror if
it carries backports and pull from there.

For squeeze nothing changed.

deb http://backports.debian.org/debian-backports/ squeeze-backports(-sloppy) main

continues to work for the whole squeeze lifetime.[/code]