deb http://ftp.us.debian.org/debian/ stretch main deb-src http://ftp.us.debian.org/debian/ stretch main deb http://ftp.us.debian.org/debian jessie-backports main deb http://security.debian.org/ stretch/updates main contrib deb-src http://security.debian.org/ stretch/updates main contrib # stretch-updates, previously known as 'volatile' deb http://ftp.us.debian.org/debian/ stretch-updates main contrib deb-src http://ftp.us.debian.org/debian/ stretch-updates main contrib