NAME

       cdist-stages - Stages used during configuration deployment

DESCRIPTION

       Starting the execution of deployment with cdist, cdist passes through different stages.

STAGE 1: TARGET INFORMATION RETRIEVAL

       In this stage information is collected about the target host using so called explorers. Every existing
       explorer is run on the target and the output of all explorers are copied back into the local cache. The
       results can be used by manifests and types.

STAGE 2: RUN THE INITIAL MANIFEST

       The initial manifest, which should be used for mappings of hosts to types, is executed. This stage
       creates objects in a cconfig database that contains the objects as defined in the manifest for the
       specific host. In this stage, no conflicts may occur, i.e. no object of the same type with the same id
       may be created, if it has different parameters.

STAGE 3: OBJECT INFORMATION RETRIEVAL

       Every object is checked whether its type has explorers and if so, these are executed on the target host.
       The results are transferred back and can be used in the following stages to decide what changes need to
       be made on the target to implement the desired state.

STAGE 4: RUN THE OBJECT MANIFEST

       Every object is checked whether its type has a executable manifest. The manifest script may generate and
       change the created objects. In other words, one type can reuse other types.

       For instance the object apache/www.example.org is of type apache, which may contain a manifest script,
       which creates new objects of type __file.

       The newly created objects are merged back into the existing tree. No conflicts may occur during the
       merge. A conflict would mean that two different objects try to create the same object, which indicates a
       broken configuration.

STAGE 5: CODE GENERATION

       In this stage for every created object its type is checked for executable gencode scripts. The gencode
       scripts generate the code to be executed on the target on stdout. If the gencode executables fail, they
       must print diagnostic messages on stderr and exit non-zero.

STAGE 6: CODE EXECUTION

       For every object the resulting code from the previous stage is transferred to the target host and
       executed there to apply the configuration changes.

STAGE 7: CACHE

       The cache stores the information from the current run for later use.

SUMMARY

       If, and only if, all the stages complete without an errors, the configuration will be applied to the
       target.

SEE ALSO

       •   cdist(1)

       •   cdist-reference(7)

COPYING

       Copyright (C) 2010-2012 Nico Schottelius, Steven Armstrong. Free use of this software is granted under
       the terms of the GNU General Public License version 3 (GPLv3).

AUTHOR

       Nico Schottelius <nico-cdist--@--schottelius.org>
           Author.

                                                   04/07/2016                                    CDIST-STAGES(7)