]# cat sources.list
deb http://de.archive.ubuntu.com/ubuntu xenial main restricted universe multiverse
#deb-src http://de.archive.ubuntu.com/ubuntu xenial main restricted universe multiverse

deb http://de.archive.ubuntu.com/ubuntu xenial-updates main restricted universe multiverse
#deb-src http://de.archive.ubuntu.com/ubuntu xenial-updates main restricted universe multiverse

deb http://de.archive.ubuntu.com/ubuntu xenial-security main restricted universe multiverse
#deb-src http://de.archive.ubuntu.com/ubuntu xenial-security main restricted universe multiverse

deb http://de.archive.ubuntu.com/ubuntu xenial-backports main restricted universe multiverse
#deb-src http://de.archive.ubuntu.com/ubuntu xenial-backports main restricted universe multiverse

# deb http://archive.canonical.com/ubuntu xenial partner
# deb-src http://archive.canonical.com/ubuntu xenial partner