1.1 --- a/README.txt Sat Mar 10 00:54:42 2012 +0100
1.2 +++ b/README.txt Sat Mar 10 01:23:44 2012 +0100
1.3 @@ -9,6 +9,12 @@
1.4 program environments, library paths, and so on. In effect, userinstall
1.5 provides a personal package manager.
1.6
1.7 +In addition, userinstall also provides tools to manage conventional chroot
1.8 +filesystem areas and User Mode Linux system images. Such capabilities are
1.9 +useful when needing to run distributions that are sufficiently different from
1.10 +the host system's distribution that the non-root approach no longer works,
1.11 +due to system library or kernel incompatibilities.
1.12 +
1.13 Contact, Copyright and Licence Information
1.14 ------------------------------------------
1.15
1.16 @@ -45,7 +51,9 @@
1.17 installations. Added --dev option for bind mounting of /dev in normal
1.18 chroot installations.
1.19 * Added support for UML instance construction from distribution
1.20 - installations, along with networking support and a uml-net script.
1.21 + installations, along with networking support and a uml-net script. Also
1.22 + added some support for booting from initrd files and installation media
1.23 + image files.
1.24
1.25 Configuration
1.26 -------------
1.27 @@ -295,6 +303,38 @@
1.28
1.29 uml-do 512M --net
1.30
1.31 +Booting into UML from Installation Media
1.32 +----------------------------------------
1.33 +
1.34 +Instead of populating a filesystem image for User Mode Linux from an existing
1.35 +distribution installation, blank images can be created as follows:
1.36 +
1.37 +uml-make-image --do-not-populate 4 512
1.38 +
1.39 +Then, an initrd file can be used together with installation media - typically
1.40 +an ISO file that would usually be burned onto a CD or DVD - such that a UML
1.41 +instance can be booted and a distribution then installed into the blank images
1.42 +from the installation media.
1.43 +
1.44 +The initrd file is typically extracted from an ISO file (for example,
1.45 +installer.iso) as follows (with superuser privileges):
1.46 +
1.47 +mkdir installer
1.48 +mount -o loop installer.iso installer
1.49 +cp installer/initrd.gz .
1.50 +umount installer
1.51 +
1.52 +This assumes that initrd.gz is found at the top level of the installation
1.53 +media's filesystem.
1.54 +
1.55 +The UML instance is then booted as follows:
1.56 +
1.57 +uml-do 512M --net --initrd initrd.gz installer.iso
1.58 +
1.59 +The blank images will appear as /dev/ubda and /dev/ubdb devices in the
1.60 +instance, not merely as partitions, and so installers may ask you if you would
1.61 +like to partition these devices still further.
1.62 +
1.63 Issues with Shared Memory
1.64 -------------------------
1.65