update mirror size

doc/fai-guide.txt

@@ -10,7 +10,6 @@ Wed, 18 Sep 2019
 :Revision: 5.8
 
 :nfsrootsize: 780
-:mirrorsize: 56
 
 ////
 <tt>  => _
@@ -1632,7 +1631,7 @@ before calling 'fai-setup' or 'fai-make-nfsroot'.
 
 FAI_DEBOOTSTRAP::
 Building the nfsroot uses the command `debootstrap(8)`. It needs the location of a Debian mirror and the
-name of the distribution (wheezy, jessie, stretch, sid) for which the basic Debian
+name of the distribution (like bullsseye, bookworm, sid) for which the basic Debian
 system should be built. Do not use different distributions here and in
 '/etc/fai/apt/sources.list'. This will create a broken nfsroot.
 
@@ -2302,8 +2301,9 @@ Then mounting the nfsroot from a FAI server using NFS v4 will work.
 The utility `mkdebmirror` footnote:[You can find the script in
 '/usr/share/doc/fai-doc/examples/utils/'] can be used for creating
 your own local Debian mirror. This script uses `debmirror(1)`. A partial Debian mirror for i386 and amd64 architecture for
-Debian 8.0 (aka jessie) without the source packages needs about
-{mirrorsize}GB of disk space. Accessing the mirror via HTTP will be the
+Debian 11.0 (aka bullseye) without the source packages needs about
+100GB of disk space. An amd64 only mirror needs about 80GB.
+Accessing the mirror via HTTP will be the
 default way in most cases. To see more output from the script call
 +mkdebmirror -v+. A root account is not necessary to create and
 maintain the Debian mirror.