---

cp -L /etc/resolv.conf /mnt/etc/resolv.conf

cat << 'EOF' > /mnt/etc/apt/sources.list
deb http://old-releases.ubuntu.com/ubuntu/ xenial main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu/ xenial-updates main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu/ xenial-security main restricted universe multiverse
EOF