lorax/docs/livemedia-creator.rst

livemedia-creator
=================

:Authors:
    Brian C. Lane <bcl@redhat.com>

livemedia-creator uses `Anaconda <https://github.com/rhinstaller/anaconda>`_,
`kickstart <https://github.com/rhinstaller/pykickstart>`_ and `Lorax
<https://github.com/rhinstaller/lorax>`_ to create bootable media that use the
same install path as a normal system installation. It can be used to make live
isos, bootable (partitioned) disk images, tarfiles, and filesystem images for
use with virtualization and container solutions like libvirt, docker, and
OpenStack.

The general idea is to use virt-install with kickstart and an Anaconda boot.iso to
install into a disk image and then use the disk image to create the bootable
media.

livemedia-creator --help will describe all of the options available. At the
minimum you need:

``--make-iso`` to create a final bootable .iso or one of the other ``--make-*`` options.

``--iso`` to specify the Anaconda install media to use with virt-install.

``--ks`` to select the kickstart file describing what to install.

To use livemedia-creator with virtualization you will need to have virt-install installed.

If you are going to be using Anaconda directly, with ``--no-virt`` mode, make sure
you have the anaconda-tui package installed.

Conventions used in this document:

``lmc`` is an abbreviation for livemedia-creator.

``builder`` is the system where livemedia-creator is being run

``image`` is the disk image being created by running livemedia-creator


livemedia-creator cmdline arguments
-----------------------------------

See the output from ``livemedia-creator --help`` for the commandline arguments.

Quickstart
----------

Run this to create a bootable live iso::

    sudo livemedia-creator --make-iso \
    --iso=/extra/iso/boot.iso --ks=./docs/rhel7-livemedia.ks

You can run it directly from the lorax git repo like this::

    sudo PATH=./src/sbin/:$PATH PYTHONPATH=./src/ ./src/sbin/livemedia-creator \
    --make-iso --iso=/extra/iso/boot.iso \
    --ks=./docs/rhel7-livemedia.ks --lorax-templates=./share/

You can observe the installation using vnc. The logs will show what port was
chosen, or you can use a specific port by passing it. eg. ``--vnc vnc:127.0.0.1:5``

This is usually a good idea when testing changes to the kickstart. lmc tries
to monitor the logs for fatal errors, but may not catch everything.


How ISO creation works
----------------------

There are 2 stages, the install stage which produces a disk or filesystem image
as its output, and the boot media creation which uses the image as its input.
Normally you would run both stages, but it is possible to stop after the
install stage, by using ``--image-only``, or to skip the install stage and use
a previously created disk image by passing ``--disk-image`` or ``--fs-image``

When creating an iso virt-install boots using the passed Anaconda installer iso
and installs the system based on the kickstart. The ``%post`` section of the
kickstart is used to customize the installed system in the same way that
current spin-kickstarts do.

livemedia-creator monitors the install process for problems by watching the
install logs. They are written to the current directory or to the base
directory specified by the --logfile command. You can also monitor the install
by using a vnc client. This is recommended when first modifying a kickstart,
since there are still places where Anaconda may get stuck without the log
monitor catching it.

The output from this process is a partitioned disk image. kpartx can be used
to mount and examine it when there is a problem with the install. It can also
be booted using kvm.

When creating an iso the disk image's / partition is copied into a formatted
filesystem image which is then used as the input to lorax for creation of the
final media.

The final image is created by lorax, using the templates in /usr/share/lorax/live/
or the live directory below the directory specified by ``--lorax-templates``. The
templates are written using the Mako template system with some extra commands
added by lorax.


Kickstarts
----------

The docs/ directory includes several example kickstarts, one to create a live
desktop iso using GNOME, and another to create a minimal disk image. When
creating your own kickstarts you should start with the minimal example, it
includes several needed packages that are not always included by dependencies.

Or you can use existing spin kickstarts to create live media with a few
changes. Here are the steps I used to convert the Fedora XFCE spin.

1. Flatten the xfce kickstart using ksflatten
2. Add zerombr so you don't get the disk init dialog
3. Add clearpart --all
4. Add swap partition
5. bootloader target
6. Add shutdown to the kickstart
7. Add network --bootproto=dhcp --activate to activate the network
   This works for F16 builds but for F15 and before you need to pass
   something on the cmdline that activate the network, like sshd:

    ``livemedia-creator --kernel-args="sshd"``

8. Add a root password::

    rootpw rootme
    network --bootproto=dhcp --activate
    zerombr
    clearpart --all
    bootloader --location=mbr
    part swap --size=512
    shutdown

9. In the livesys script section of the %post remove the root password. This
   really depends on how the spin wants to work. You could add the live user
   that you create to the %wheel group so that sudo works if you wanted to.

    ``passwd -d root > /dev/null``

10. Remove /etc/fstab in %post, dracut handles mounting the rootfs

    ``cat /dev/null > /dev/fstab``

    Do this only for live iso's, the filesystem will be mounted read only if
    there is no /etc/fstab

11. Don't delete initramfs files from /boot in %post
12. When creating live iso's you need to have, at least, these packages in the %package section::
    dracut-config-generic
    dracut-live
    -dracut-config-rescue
    grub-efi
    memtest86+
    syslinux

One drawback to using virt-install is that it pulls the packages from the repo
each time you run it. To speed things up you either need a local mirror of the
packages, or you can use a caching proxy. When using a proxy you pass it to
livemedia-creator like this:

    ``--proxy=http://proxy.yourdomain.com:3128``

You also need to use a specific mirror instead of mirrormanager so that the
packages will get cached, so your kickstart url would look like:

    ``url --url="http://dl.fedoraproject.org/pub/fedora/linux/development/rawhide/x86_64/os/"``

You can also add an update repo, but don't name it updates. Add --proxy to it
as well.


Anaconda image install (no-virt)
--------------------------------

You can create images without using virt-install by passing ``--no-virt`` on
the cmdline. This will use Anaconda's directory install feature to handle the
install.  There are a couple of things to keep in mind when doing this:

1. It will be most reliable when building images for the same release that the
   host is running. Because Anaconda has expectations about the system it is
   running under you may encounter strange bugs if you try to build newer or
   older releases.

2. Make sure selinux is set to permissive or disabled. It won't install
   correctly with selinux set to enforcing yet.

3. It may totally trash your host. So far I haven't had this happen, but the
   possibility exists that a bug in Anaconda could result in it operating on
   real devices. I recommend running it in a virt or on a system that you can
   afford to lose all data from.

The logs from anaconda will be placed in an ./anaconda/ directory in either
the current directory or in the directory used for --logfile

Example cmdline:

``sudo livemedia-creator --make-iso --no-virt --ks=./rhel7-livemedia.ks``

.. note::
    Using no-virt to create a partitioned disk image (eg. --make-disk or
    --make-vagrant) will only create disks usable on the host platform (BIOS
    or UEFI). You can create BIOS partitioned disk images on UEFI by using
    virt.


AMI Images
----------

Amazon EC2 images can be created by using the --make-ami switch and an appropriate
kickstart file. All of the work to customize the image is handled by the kickstart.
The example currently included was modified from the cloud-kickstarts version so
that it would work with livemedia-creator.

Example cmdline:

``sudo livemedia-creator --make-ami --iso=/path/to/boot.iso --ks=./docs/rhel7-livemedia-ec2.ks``

This will produce an ami-root.img file in the working directory.

At this time I have not tested the image with EC2. Feedback would be welcome.


Appliance Creation
------------------

livemedia-creator can now replace appliance-tools by using the --make-appliance
switch. This will create the partitioned disk image and an XML file that can be
used with virt-image to setup a virtual system.

The XML is generated using the Mako template from
/usr/share/lorax/appliance/libvirt.xml You can use a different template by
passing ``--app-template <template path>``

Documentation on the Mako template system can be found at the `Mako site
<http://docs.makotemplates.org/en/latest/index.html>`_

The name of the final output XML is appliance.xml, this can be changed with
``--app-file <file path>``

The following variables are passed to the template:

    ``disks``
       A list of disk_info about each disk.
       Each entry has the following attributes:

        ``name``
        base name of the disk image file

        ``format``
        "raw"

        ``checksum_type``
        "sha256"

        ``checksum``
        sha256 checksum of the disk image

    ``name``
    Name of appliance, from --app-name argument

    ``arch``
    Architecture

    ``memory``
    Memory in KB (from ``--ram``)

    ``vcpus``
    from ``--vcpus``

    ``networks``
    list of networks from the kickstart or []

    ``title``
    from ``--title``

    ``project``
    from ``--project``

    ``releasever``
    from ``--releasever``

The created image can be imported into libvirt using:

    ``virt-image appliance.xml``

You can also create qcow2 appliance images using ``--image-type=qcow2``, for example::

    sudo livemedia-creator --make-appliance --iso=/path/to/boot.iso --ks=./docs/rhel7-minimal.ks \
    --image-type=qcow2 --app-file=minimal-test.xml --image-name=minimal-test.img


Filesystem Image Creation
-------------------------

livemedia-creator can be used to create un-partitined filesystem images using
the ``--make-fsimage`` option. As of version 21.8 this works with both virt and
no-virt modes of operation. Previously it was only available with no-virt.

Kickstarts should have a single / partition with no extra mountpoints.

    ``livemedia-creator --make-fsimage --iso=/path/to/boot.iso --ks=./docs/rhel7-minimal.ks``

You can name the output image with ``--image-name`` and set a label on the filesystem with ``--fs-label``


TAR File Creation
-----------------

The ``--make-tar`` command can be used to create a tar of the root filesystem. By
default it is compressed using xz, but this can be changed using the
``--compression`` and ``--compress-arg`` options. This option works with both virt and
no-virt install methods.

As with ``--make-fsimage`` the kickstart should be limited to a single / partition.

For example::

    livemedia-creator --make-tar --iso=/path/to/boot.iso --ks=./docs/rhel7-minimal.ks \
    --image-name=rhel7-root.tar.xz


Live Image for PXE Boot
-----------------------

The ``--make-pxe-live`` command will produce squashfs image containing live root
filesystem that can be used for pxe boot. Directory with results will contain
the live image, kernel image, initrd image and template of pxe configuration
for the images.


Atomic Live Image for PXE Boot
------------------------------

The ``--make-ostree-live`` command will produce the same result as ``--make-pxe-live``
for installations of Atomic Host.  Example kickstart for such an installation
using Atomic installer iso with local repo included in the image can be found
in docs/rhel-atomic-pxe-live.ks.

The PXE images can also be created with ``--no-virt`` by using the example
kickstart in docs/rhel-atomic-pxe-live-novirt.ks. This also works inside the
mock environment.


Debugging problems
------------------

Sometimes an installation will get stuck. When using virt-install the logs will
be written to ./virt-install.log and most of the time any problems that happen
will be near the end of the file. lmc tries to detect common errors and will
cancel the installation when they happen. But not everything can be caught.
When creating a new kickstart it is helpful to use vnc so that you can monitor
the installation as it happens, and if it gets stuck without lmc detecting the
problem you can switch to tty1 and examine the system directly.

If it does get stuck the best way to cancel is to use kill -9 on the virt-install pid,
lmc will detect that the process died and cleanup.

If lmc didn't handle the cleanup for some reason you can do this:
1. ``sudo umount /tmp/lmc-XXXX`` to unmount the iso from its mountpoint.
2. ``sudo rm -rf /tmp/lmc-XXXX``
3. ``sudo rm /var/tmp/lmc-disk-XXXXX`` to remove the disk image.

Note that lmc uses the lmc- prefix for all of its temporary files and
directories to make it easier to find and clean up leftovers.

The logs from the virt-install run are stored in virt-install.log, logs from
livemedia-creator are in livemedia.log and program.log

You can add ``--image-only`` to skip the .iso creation and examine the resulting
disk image. Or you can pass ``--keep-image`` to keep it around after the iso has
been created.

Cleaning up aborted ``--no-virt`` installs can sometimes be accomplished by
running the ``anaconda-cleanup`` script. As of Fedora 18 anaconda is
multi-threaded and it can sometimes become stuck and refuse to exit. When this
happens you can usually clean up by first killing the anaconda process then
running ``anaconda-cleanup``.


Hacking
-------

Development on this will take place as part of the lorax project, and on the
anaconda-devel-list mailing list, and `on github <https://github.com/rhinstaller/lorax>`_

Feedback, enhancements and bugs are welcome.  You can use `bugzilla
<https://bugzilla.redhat.com/enter_bug.cgi?product=Fedora&component=lorax>`_ to
report bugs against the lorax component.