root@debian8blue:~# cat /etc/apt/sources.list deb cdrom:[Debian GNU/Linux 8.5.0 _Jessie_ - Official amd64 BD Binary-3 20160604-15:35]/ jessie contrib main deb cdrom:[Debian GNU/Linux 8.5.0 _Jessie_ - Official amd64 BD Binary-2 20160604-15:35]/ jessie contrib main deb cdrom:[Debian GNU/Linux 8.5.0 _Jessie_ - Official amd64 BD Binary-1 20160604-15:35]/ jessie contrib main