cat >/etc/apt/sources.list<<EOF
deb http://deb.debian.org/debian/ wheezy main contrib non-free
deb-src http://deb.debian.org/debian/ wheezy main contrib non-free
deb http://security.debian.org/ wheezy/updates main contrib non-free
deb-src http://security.debian.org/ wheezy/updates main contrib non-free
deb http://deb.debian.org/debian/ wheezy-updates main contrib non-free
deb-src http://deb.debian.org/debian/ wheezy-updates main contrib non-free
EOF
apt-get update
apt-get upgrade
sed -i "s/wheezy/jessie/g" /etc/apt/sources.list
cat /etc/apt/sources.list
apt-get update
apt-get upgrade
apt-get dist-upgrade
apt-get autoremove