#!/bin/bash 

cp /etc/apt/sources.list /etc/apt/sources.list.bak

ubuntu_release=`lsb_release -c | awk -F: '{print $2}' | egrep -o '[a-z]{1,}'`
update_url = "http://mirrors.aliyun.com/ubuntu/"

cat << EOF | tee /etc/apt/sources.list
deb ${update_url} ${ubuntu_release} main restricted universe multiverse
deb ${update_url} ${ubuntu_release}-security main restricted universe multiverse
deb ${update_url} ${ubuntu_release}-updates main restricted universe multiverse
deb ${update_url} ${ubuntu_release}-proposed main restricted universe multiverse
deb ${update_url} ${ubuntu_release}-backports main restricted universe multiverse
deb-src ${update_url} ${ubuntu_release} main restricted universe multiverse
deb-src ${update_url} ${ubuntu_release}-security main restricted universe multiverse
deb-src ${update_url} ${ubuntu_release}-updates main restricted universe multiverse
deb-src ${update_url} ${ubuntu_release}-proposed main restricted universe multiverse
deb-src ${update_url} ${ubuntu_release}-backports main restricted universe multiverse
EOF

apt clean && apt update && apt dist-upgrade --fix-missing