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@@ -8,3 +8,44 @@ If you're reading this, I hope maybe some of this will be useful to you?
 -w
 
 Will Woods <wwoods@redhat.com>
+
+HOW IT WORKS:
+
+Before you start, you should edit testboot.conf and set $dracutdir and $cdrom.
+
+The first time you run testboot.sh, , it will open up the configured CDROM
+image and pull out some files:
+
+  vmlinuz
+  vmlinuz.kv
+  initramfs.img.orig
+  initramfs.orig/
+  /lib/modules/$(kernel version)/
+
+It then rebuilds the initramfs using the dracut in $dracutdir, and whatever
+$dracut_opts you set in testboot.conf. This creates:
+
+  initramfs/
+
+Next, if there is an updates/ directory, its contents are copied into
+initramfs/. And then we create:
+
+  initrd.img
+
+which is just a compressed cpio archive of initramfs/.
+
+Finally, we run virt-install, booting the vmlinuz+initrd.img (PXE-style) with
+any kernel arguments given on the commandline.
+
+TIPS:
+
+To force a rebuild of the initramfs, 'rm -rf initramfs'.
+
+Remember that the files in 'updates/' are applied to the *initrd*. If you want
+to apply updates to the anaconda runtime put them in 'updates/updates'. For
+example, adding 'updates/updates/usr/bin/free' would add the 'free' binary to
+the anaconda environment.
+
+BUGS:
+
+If you remove something from updates/, it doesn't get removed from initramfs/.