cdist/doc/man/man7/cdist-manifest.text

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cdist-manifest(7)
=================
Nico Schottelius <nico-cdist--@--schottelius.org>
NAME
----
cdist-manifest - Define types to be used
DEFINE STATE IN THE INITIAL MANIFEST
------------------------------------
The **initial manifest** is the entry point for cdist to find out, which
**objects** to configure on the selected host. Objects are instances of
**types**, like in object orientated programming languages.
An object is represented by the
type + slash + object name: ***__file/etc/cdist-configured*** is an
object of the type ***__file*** with the name ***etc/cdist-configured***.
Cdist searches for the initial manifest at **conf/manifest/init** and
executes it as a shell script using **/bin/sh -e**.
Within this initial manifest, you define, which objects should be
created on which host. To distinguish between hosts, you can use the
environment variable **__target_host**. Let's have a look at a simple
example:
--------------------------------------------------------------------------------
__cdistmarker
case "$__target_host" in
localhost)
__directory /home/services/kvm-vm --parents yes
;;
esac
--------------------------------------------------------------------------------
This manifest says: Independent of the host, always use the type
***__cdistmarker***, which creates the file **/etc/cdist-configured**,
with the timestamp as content.
The directory ***/home/services/kvm-vm***, including all parent directories,
is only created on the host ***localhost***.
As you can see, there is no magic involved, the manifest is simple shell code that
utilises cdist types. Every available type can be executed like a normal
command. Use **ls conf/type** to get a list of available types. If you have
setup the MANPATH correctly as, you can use **man cdist-reference** to access
the reference with pointers to the manpages.
DESCRIPTION
-----------
Manifests exist to define which configurations should be applied to a specific
host as well as to define which configurations should be applied within a
type. Manifests are executed locally and the resulting objects are stored in
an internal database.
The same object can be redefined in multiple different manifests as long as
the parameters are exactly the same.
In general, manifests are used to define which types are used depending
on given conditions.
EXAMPLE
-------
The initial manifest may for instance contain the following code:
--------------------------------------------------------------------------------
# Always create this file, so other sysadmins know cdist is used.
__file /etc/cdist-configured --type file
case "$__target_host" in
my.server.name)
__file /root/bin/ --type directory
__file /etc/issue.net --type file --source "$__manifest/issue.net
;;
esac
--------------------------------------------------------------------------------
The manifest of the type "nologin" may look like this:
--------------------------------------------------------------------------------
__file /etc/nologin --type file --source "$__type/files/default.nologin"
--------------------------------------------------------------------------------
DEPENDENCIES
------------
If you want to describe that something requires something else, just
setup the variable "require" to contain the requirements. Multiple
requirements can be added white space seperated.
--------------------------------------------------------------------------------
# No dependency
__file /etc/cdist-configured
# Require above object
require="__file/etc/cdist-configured" __link /tmp/cdist-testfile \
--source /etc/cdist-configured --type symbolic
# Require two objects
require="__file/etc/cdist-configured __link/tmp/cdist-testfile" \
__file /tmp/cdist-another-testfile
--------------------------------------------------------------------------------
SEE ALSO
--------
- cdist-type(7)
COPYING
-------
Copyright \(C) 2010-2012 Nico Schottelius. Free use of this software is
granted under the terms of the GNU General Public License version 3 (GPLv3).