pi@Raspi1:~ $ sudo nano /etc/apt/apt.conf
  GNU nano 2.2.6                               Fichier : /etc/apt/apt.conf

APT::Default-Release "jessie";

pi@Raspi1:~ $ cat /etc/apt/apt.conf.d/*
APT
{
  NeverAutoRemove
  {
        "^firmware-linux.*";
        "^linux-firmware$";
  };

  VersionedKernelPackages
  {
        # linux kernels
        "linux-image";
        "linux-headers";
        "linux-image-extra";
        "linux-signed-image";
        # kfreebsd kernels
        "kfreebsd-image";
        "kfreebsd-headers";
        # hurd kernels
        "gnumach-image";
        # (out-of-tree) modules
        ".*-modules";
        ".*-kernel";
        "linux-backports-modules-.*";
        # tools
        "linux-tools";
  };

  Never-MarkAuto-Sections
  {
        "metapackages";
        "restricted/metapackages";
        "universe/metapackages";
        "multiverse/metapackages";
        "oldlibs";
        "restricted/oldlibs";
        "universe/oldlibs";
        "multiverse/oldlibs";
  };
};
// DO NOT EDIT! File autogenerated by /etc/kernel/postinst.d/apt-auto-removal
APT::NeverAutoRemove
{
   "^linux-image-3\.16\.0-4-amd64$";
   "^linux-image-4\.4\.50-v7+$";
   "^linux-headers-3\.16\.0-4-amd64$";
   "^linux-headers-4\.4\.50-v7+$";
   "^linux-image-extra-3\.16\.0-4-amd64$";
   "^linux-image-extra-4\.4\.50-v7+$";
   "^linux-signed-image-3\.16\.0-4-amd64$";
   "^linux-signed-image-4\.4\.50-v7+$";
   "^kfreebsd-image-3\.16\.0-4-amd64$";
   "^kfreebsd-image-4\.4\.50-v7+$";
   "^kfreebsd-headers-3\.16\.0-4-amd64$";
   "^kfreebsd-headers-4\.4\.50-v7+$";
   "^gnumach-image-3\.16\.0-4-amd64$";
   "^gnumach-image-4\.4\.50-v7+$";
   "^.*-modules-3\.16\.0-4-amd64$";
   "^.*-modules-4\.4\.50-v7+$";
   "^.*-kernel-3\.16\.0-4-amd64$";
   "^.*-kernel-4\.4\.50-v7+$";
   "^linux-backports-modules-.*-3\.16\.0-4-amd64$";
   "^linux-backports-modules-.*-4\.4\.50-v7+$";
   "^linux-tools-3\.16\.0-4-amd64$";
   "^linux-tools-4\.4\.50-v7+$";
};
DPkg::Pre-Install-Pkgs { "/usr/bin/apt-listchanges --apt || test $? -ne 10"; };
DPkg::Tools::Options::/usr/bin/apt-listchanges::Version "2";
// THIS FILE IS USED TO INFORM PACKAGEKIT
// THAT THE UPDATE-INFO MIGHT HAVE CHANGED

// Whenever dpkg is called we might have different updates
// i.e. if an user removes a package that had an update
DPkg::Post-Invoke {
"/usr/bin/test -e /usr/share/dbus-1/system-services/org.freedesktop.PackageKit.service && /usr/bin/test -S /var/run/dbus/system_bus_socket && /usr/bin/gdbus call --system --dest org.freedesktop.PackageKit --object-path /org/freedesktop/PackageKit --timeout 4 --method org.freedesktop.PackageKit.StateHasChanged cache-update > /dev/null; /bin/echo > /dev/null";
};

// When Apt's cache is updated (i.e. apt-cache update)
APT::Update::Post-Invoke-Success {
"/usr/bin/test -e /usr/share/dbus-1/system-services/org.freedesktop.PackageKit.service && /usr/bin/test -S /var/run/dbus/system_bus_socket && /usr/bin/gdbus call --system --dest org.freedesktop.PackageKit --object-path /org/freedesktop/PackageKit --timeout 4 --method org.freedesktop.PackageKit.StateHasChanged cache-update > /dev/null; /bin/echo > /dev/null";
};
# never use pdiffs. Current implementation is very slow on low-powered devices
Acquire::PDiffs "0";

# download up to 5 pdiffs:
#Acquire::PDiffs::FileLimit "5";
// Pre-configure all packages with debconf before they are installed.
// If you don't like it, comment it out.
DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt || true";};

pi@Raspi1:~ $ sudo apt-get install certbot -s
Lecture des listes de paquets... Fait
Construction de l'arbre des dépendances
Lecture des informations d'état... Fait
Les paquets supplémentaires suivants seront installés :
  python-acme python-certbot python-configargparse python-configobj python-dnspython python-funcsigs python-mock python-openssl
  python-parsedatetime python-pbr python-pyicu python-rfc3339 python-tz python-zope.component python-zope.event python-zope.interface
Paquets suggérés :
  python-certbot-apache python-certbot-doc python-acme-doc python-configobj-doc python-funcsigs-doc python-mock-doc python-openssl-doc
  python-openssl-dbg
Les NOUVEAUX paquets suivants seront installés :
  certbot python-acme python-certbot python-configargparse python-configobj python-dnspython python-funcsigs python-mock
  python-parsedatetime python-pbr python-pyicu python-rfc3339 python-tz python-zope.component python-zope.event python-zope.interface
Les paquets suivants seront mis à jour :
  python-openssl
1 mis à jour, 16 nouvellement installés, 0 à enlever et 86 non mis à jour.
Inst python-configargparse (0.11.0-1~bpo8+1 Debian Backports:jessie-backports [all])
Inst python-configobj (5.0.6-1 Raspbian:stable [all])
Inst python-dnspython (1.15.0-1~bpo8+1 Debian Backports:jessie-backports [all])
Inst python-funcsigs (1.0.2-3~bpo8+1 Debian Backports:jessie-backports [all])
Inst python-openssl [0.13.1-2] (16.0.0-1~bpo8+1 Debian Backports:jessie-backports [all])
Inst python-parsedatetime (1.4-1 Raspbian:stable [all])
Inst python-pbr (1.8.0-4.1~bpo8+1 Debian Backports:jessie-backports [all])
Inst python-pyicu (1.8-1 Raspbian:stable [armhf])
Inst python-tz (2012c+dfsg-0.1 Raspbian:stable [all])
Inst python-rfc3339 (1.0-4~bpo8+1 Debian Backports:jessie-backports [all])
Inst python-zope.interface (4.1.1-3.1 Raspbian:stable [armhf])
Inst python-mock (2.0.0-3~bpo8+1 Debian Backports:jessie-backports [all])
Inst python-acme (0.10.2-1~bpo8+2 Debian Backports:jessie-backports [all])
Inst python-zope.event (4.0.3-2 Raspbian:stable [all])
Inst python-zope.component (4.2.1-2 Raspbian:stable [all])
Inst python-certbot (0.10.2-1~bpo8+1 Debian Backports:jessie-backports [all])
Inst certbot (0.10.2-1~bpo8+1 Debian Backports:jessie-backports [all])
Conf python-configargparse (0.11.0-1~bpo8+1 Debian Backports:jessie-backports [all])
Conf python-configobj (5.0.6-1 Raspbian:stable [all])
Conf python-dnspython (1.15.0-1~bpo8+1 Debian Backports:jessie-backports [all])
Conf python-funcsigs (1.0.2-3~bpo8+1 Debian Backports:jessie-backports [all])
Conf python-openssl (16.0.0-1~bpo8+1 Debian Backports:jessie-backports [all])
Conf python-parsedatetime (1.4-1 Raspbian:stable [all])
Conf python-pbr (1.8.0-4.1~bpo8+1 Debian Backports:jessie-backports [all])
Conf python-pyicu (1.8-1 Raspbian:stable [armhf])
Conf python-tz (2012c+dfsg-0.1 Raspbian:stable [all])
Conf python-rfc3339 (1.0-4~bpo8+1 Debian Backports:jessie-backports [all])
Conf python-zope.interface (4.1.1-3.1 Raspbian:stable [armhf])
Conf python-mock (2.0.0-3~bpo8+1 Debian Backports:jessie-backports [all])
Conf python-acme (0.10.2-1~bpo8+2 Debian Backports:jessie-backports [all])
Conf python-zope.event (4.0.3-2 Raspbian:stable [all])
Conf python-zope.component (4.2.1-2 Raspbian:stable [all])
Conf python-certbot (0.10.2-1~bpo8+1 Debian Backports:jessie-backports [all])
Conf certbot (0.10.2-1~bpo8+1 Debian Backports:jessie-backports [all])