+.jessie/stretch/buster release
+================================================================================
+[1] Please notice that releases like jessie, stretch and buster are unsupported releases within Debian nowadays.
+grml-debootstrap can handle the releases but you really should not use them anymore unless you really know what you are doing.
+Even older versions are also entirely unsupported by grml-debootstrap.
+
+Choose the current Debian stable version instead.
+See https://wiki.debian.org/DebianReleases for the list of supported releases.
+
+Notice that you need to specify a specific mirror providing old releases, the default (http://deb.debian.org/debian) doesn't provide them any longer.
+Set the mirror to e.g. http://archive.debian.org/debian/ if you don't have your own Debian mirror.
+
+Older releases might also fail to install when running on top of recent kernel versions,
+throwing segfaults during debootstrap. This can be identified by the following messages inside kernel log (check with 'dmesg'):
+
+ dpkg[...] vsyscall attempted with vsyscall=none ip:[...]
+ dpkg[...]: segfault at [...]
+
+To work around this issue boot your system with the kernel boot option 'vsyscall=emulate'.
+================================================================================
+
+[NOTE]
+.unstable and testing releases