Configuration of instance creation
----------------------------------
+Note: the minimum disk size accepted is 256MB, as ``debootstrap``
+requires disk space both for downloading the packages and installing
+them.
+
The kind of instance created can be customized via a settings file. This
file is not installed by default, as the instance creation will work
without it. The creation scripts will look for it in
- ARCH: either i386 or amd64, otherwise your current architecture will
be used
- SUITE: the actual OS to be installed; the current default is Debian
- *lenny*, and you can choose any of the OSes supported deboostrap (on
+ *wheezy*, and you can choose any of the OSes supported deboostrap (on
Debian, look into /usr/share/deboostrap/scripts)
- EXTRAPKGS: most OSes will need some extra packages installed to make
them work nicely under Xen; the example file containts a few
suggestions
-- CUSTOMIZE_DIR: a directory containing customization script for the instance.
- (by default $sysconfdir/ganeti/instance-debootstrap.d) See "Customization of
- the instance" below.
+- COMPONENTS: if defined, overrides the default debootstrap components
+ ("main"); this can be helpful e.g. by using "main,contrib,nonfree" for
+ Debian, or "main,universe" for Ubuntu
+- CUSTOMIZE_DIR: a directory containing customization script for the
+ instance. (by default $sysconfdir/ganeti/instance-debootstrap/hooks)
+ See "Customization of the instance" below.
- GENERATE_CACHE: if 'yes' (the default), the installation process will
save and reuse a cache file to speed reinstalls (located under
$localstatedir/cache/ganeti-instance-debootstrap)
model of using this OS but currently the OS interface in ganeti is
limiting.
+Creating OS variants
+--------------------
+
+Every Ganeti OS supports variants, so it's possible to define custom OS
+variants with instance-debootstrap as well. First, an additional variant has
+to be defined in ``$osdir/debootstrap/variants.list`` (with ``$osdir`` being
+``/usr/share/ganeti/os`` by default). Secondly, you can configure this
+instance variant in
+``$sysconfdir/ganeti/instance-debootstrap/variants/$variant.conf``, overriding
+the settings mentioned in the previous section.
+
+To use the newly created instance variant, specify it in ``gnt-instance`` like
+this::
+
+ gnt-instance add -o debootstrap+precise ...
+
+Example
++++++++
+
+To create a Ubuntu 12.04 (precise) instance variant, add the following to
+``$osdir/debootstrap/variants.list``::
+
+ precise
+
+Now create the file
+``$sysconfdir/ganeti/instance-debootstrap/variants/precise.conf`` with the
+following content::
+
+ MIRROR="http://archive.ubuntu.com/ubuntu/"
+ SUITE="precise"
+ COMPONENTS="main,universe"
+ ARCH="amd64"
+
+You can create Ubuntu 12.04 instances as follows::
+
+ gnt-instance add -t plain -o debootstrap+precise --disk 0:size=10000m -n node1.example.com instance1.example.com
+
+For this to work, make sure that you have the appropriate debootstrap script
+for precise (or just create a symlink called ``precise`` to ``gutsy`` in
+``/usr/share/debootstrap/scripts``).
+
+Instance creation parameters
+----------------------------
+
+Some aspects of the created instance can be conrolled via parameters at
+instance creation time with the ``-O`` parameter of ``gnt-instance``.
+
+The supported parameters are:
+
+- filesystem: the filesystem type to use for the root partition. This has to
+ be a filesystem type supported by ``mke2fs``. The default is 'ext4'.
+
Customization of the instance
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-If run-parts is in the os create script, and the CUSTOMIZE_DIR (by default
-$sysconfdir/ganeti/instance-debootstrap.d, /etc/ganeti/instance-debootstrap.d
-if you configured the os with --sysconfdir=/etc) directory exists any
-executable whose name matches the run-parts execution rules (quoting
-run-parts(8): the names must consist entirely of upper and lower case
-letters, digits, underscores, and hyphens) is executed to allow further
-personalization of the installation. The following environment variables are
-passed, in addition to the ones ganeti passes to the OS scripts:
+If run-parts is in the os create script, and the CUSTOMIZE_DIR (by
+default $sysconfdir/ganeti/instance-debootstrap/hooks,
+/etc/ganeti/instance-debootstrap/hooks if you configured the os with
+--sysconfdir=/etc) directory exists any executable whose name matches
+the run-parts execution rules (quoting run-parts(8): the names must
+consist entirely of upper and lower case letters, digits, underscores,
+and hyphens) is executed to allow further personalization of the
+installation. The following environment variables are passed, in
+addition to the ones ganeti passes to the OS scripts:
TARGET: directory in which the filesystem is mounted
-SUITE: suite installed by debootstrap (eg: lenny)
+SUITE: suite installed by debootstrap (eg: wheezy)
ARCH: target architecture
PARTITION_STYLE: style of the disk partitioning (see above)
EXTRA_PKGS: extra packages installed by debootstrap
won't be able to umount the filesystem from the directory, and hand the
instance back to Ganeti.
+Example
++++++++
+
+The root password can be automatically set when the instance is created. In
+order to do this, the ``examples/hooks/defaultpasswords`` file has to be copied
+to ``$sysconfdir/ganeti/instance-debootstrap/hooks/``, and its data file
+``examples/hooks/confdata/defaultpasswords`` has to be copied to
+``$sysconfdir/ganeti/instance-debootstrap/hooks/confdata/`` and modified
+accordingly to one's own need. The file syntax is such that each line represent
+a user, with the format::
+
+ username:password
+
+After copying the two files, just running the instance creation as usual will
+automatically cause their execution.
Caching
~~~~~~~
definitions to /etc/network/interfaces
- after configuring the network, it is recommended to run ``apt-get
update`` so that signatures for the release files are picked up
+
+.. vim: set textwidth=72 :
+.. Local Variables:
+.. mode: rst
+.. fill-column: 72
+.. End:
projects / ext/instance-debootstrap.git / blobdiff