Otherwise executing 'grml-live -s jessie' fails hard
--- /dev/null
+# official debian repository:
+ deb http://ftp.debian.org/debian/ jessie main contrib non-free
+ deb-src http://ftp.debian.org/debian/ jessie main contrib non-free
+
+# security updates:
+ deb http://security.debian.org/ jessie/updates main contrib
+ deb-src http://security.debian.org/ jessie/updates main contrib
+
+# backports:
+ deb http://ftp.debian.org/debian/ jessie-backports main contrib non-free
+ deb-src http://ftp.debian.org/debian/ jessie-backports main contrib non-free