6 export DEBIAN_FRONTEND
=noninteractive
12 sed -i -e 's/http:\/\/deb/https:\/\/deb/g' /etc
/apt
/sources.list
13 echo 'deb https://deb.debian.org/debian stretch-backports main' >/etc
/apt
/sources.list.d
/backports.list
17 # Use newer packages from backports by default
18 cat >/etc
/apt
/preferences
<<EOF
20 Pin: release a=stretch-backports
24 apt-get dist-upgrade
-y
26 apt-get
install -y --no-remove \
57 ############### Uninstall unused packages
59 apt-get autoremove
-y --purge