deb http://deb.debian.org/debian stretch maindeb-src http://deb.debian.org/debian stretch maindeb http://security.debian.org/debian-security/ stretch/updates maindeb-src http://security.debian.org/debian-security/ stretch/updates maindeb http://deb.debian.org/debian stretch-updates maindeb-src http://deb.debian.org/debian stretch-updates main