Separate configuration docs from usage

This commit is contained in:
Mark Goddard 2017-05-23 21:04:51 +01:00
parent 9033145285
commit 0c08dead53
3 changed files with 106 additions and 105 deletions

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=============
Configuration
=============
This section covers configuration of Kayobe. As an Ansible-based project,
Kayobe is for the most part configured using YAML files.
Configuration Location
======================
Kayobe configuration is by default located in ``/etc/kayobe`` on the Ansible
control host. This location can be overridden to a different location to avoid
touching the system configuration directory by setting the environment variable
``KAYOBE_CONFIG_PATH``. Similarly, kolla configuration on the Ansible control
host will by default be located in ``/etc/kolla`` and can be overridden via
``KOLLA_CONFIG_PATH``.
Configuration Directory Layout
==============================
The Kayobe configuration directory contains Ansible ``extra-vars`` files and
the Ansible inventory. An example of the directory structure is as follows::
extra-vars1.yml
extra-vars2.yml
inventory/
group_vars/
group1-vars
group2-vars
groups
host_vars/
host1-vars
host2-vars
hosts
Configuration Patterns
======================
Ansible's variable precedence rules are `fairly well documented
<http://docs.ansible.com/ansible/playbooks_variables.html#variable-precedence-where-should-i-put-a-variable>`_
and provide a mechanism we can use for providing site localisation and
customisation of OpenStack in combination with some reasonable default values.
For global configuration options, Kayobe typically uses the following patterns:
- Playbook group variables for the *all* group in
``<kayobe repo>/ansible/group_vars/all/*`` set **global defaults**. These
files should not be modified.
- Playbook group variables for other groups in
``<kayobe repo>/ansible/group_vars/<group>/*`` set **defaults for some subsets
of hosts**. These files should not be modified.
- Extra-vars files in ``${KAYOBE_CONFIG_PATH}/*.yml`` set **custom values
for global variables** and should be used to apply global site localisation
and customisation. By default these variables are commented out.
Additionally, variables can be set on a per-host basis using inventory host
variables files in ``${KAYOBE_CONFIG_PATH}/inventory/host_vars/*``. It should
be noted that variables set in extra-vars files take precedence over per-host
variables.
Configuring Kayobe
==================
From a checkout of the Kayobe repository, the baseline Kayobe configuration
should be copied to the Kayobe configuration path::
$ cp -r etc/ ${KAYOBE_CONFIG_PATH:-/etc/kayobe}
Once in place, each of the YAML and inventory files should be manually
inspected and configured as required.
Inventory
----------
The inventory should contain the following hosts:
Control host
This should be localhost and should be a member of the ``config-mgmt``
group.
Seed hypervisor
If provisioning a seed VM, a host should exist for the hypervisor that
will run the VM, and should be a member of the ``seed-hypervisor`` group.
Seed
The seed host, whether provisioned as a VM by Kayobe or externally managed,
should exist in the ``seed`` group.
Cloud hosts and bare metal compute hosts are not required to exist in the
inventory.
Site Localisation and Customisation
-----------------------------------
Site localisation and customisation is applied using Ansible extra-vars files
in ``${KAYOBE_CONFIG_PATH}/*.yml``.
Encryption of Secrets
---------------------
Kayobe supports the use of `Ansible vault
<http://docs.ansible.com/ansible/playbooks_vault.html>`_ to encrypt sensitive
information in its configuration. The ``ansible-vault`` tool should be used to
manage individual files for which encryption is required. Any of the
configuration files may be encrypted. Since encryption can make working with
Kayobe difficult, it is recommended to follow `best practice
<http://docs.ansible.com/ansible/playbooks_best_practices.html#best-practices-for-variables-and-vaults>`_,
adding a layer of indirection and using encryption only where necessary.

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architecture architecture
installation installation
configuration
usage usage
Developer Documentation Developer Documentation

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@ -9,111 +9,6 @@ hypervisor has access to the bare metal nodes that will form the OpenStack
control plane. Finally, we assume that the control plane nodes have access to control plane. Finally, we assume that the control plane nodes have access to
the bare metal nodes that will form the workload node pool. the bare metal nodes that will form the workload node pool.
Configuration
=============
As an Ansible-based project, Kayobe is for the most part configured using YAML
files.
Configuration Location
----------------------
Kayobe configuration is by default located in ``/etc/kayobe`` on the Ansible
control host. This location can be overridden to a different location to avoid
touching the system configuration directory by setting the environment variable
``KAYOBE_CONFIG_PATH``. Similarly, kolla configuration on the Ansible control
host will by default be located in ``/etc/kolla`` and can be overridden via
``KOLLA_CONFIG_PATH``.
Configuration Directory Layout
------------------------------
The Kayobe configuration directory contains Ansible ``extra-vars`` files and
the Ansible inventory. An example of the directory structure is as follows::
extra-vars1.yml
extra-vars2.yml
inventory/
group_vars/
group1-vars
group2-vars
groups
host_vars/
host1-vars
host2-vars
hosts
Configuration Patterns
----------------------
Ansible's variable precedence rules are `fairly well documented
<http://docs.ansible.com/ansible/playbooks_variables.html#variable-precedence-where-should-i-put-a-variable>`_
and provide a mechanism we can use for providing site localisation and
customisation of OpenStack in combination with some reasonable default values.
For global configuration options, Kayobe typically uses the following patterns:
- Playbook group variables for the *all* group in
``<kayobe repo>/ansible/group_vars/all/*`` set **global defaults**. These
files should not be modified.
- Playbook group variables for other groups in
``<kayobe repo>/ansible/group_vars/<group>/*`` set **defaults for some subsets
of hosts**. These files should not be modified.
- Extra-vars files in ``${KAYOBE_CONFIG_PATH}/*.yml`` set **custom values
for global variables** and should be used to apply global site localisation
and customisation. By default these variables are commented out.
Additionally, variables can be set on a per-host basis using inventory host
variables files in ``${KAYOBE_CONFIG_PATH}/inventory/host_vars/*``. It should
be noted that variables set in extra-vars files take precedence over per-host
variables.
Configuring Kayobe
------------------
From a checkout of the Kayobe repository, the baseline Kayobe configuration
should be copied to the Kayobe configuration path::
$ cp -r etc/ ${KAYOBE_CONFIG_PATH:-/etc/kayobe}
Once in place, each of the YAML and inventory files should be manually
inspected and configured as required.
Inventory
^^^^^^^^^
The inventory should contain the following hosts:
Control host
This should be localhost and should be a member of the ``config-mgmt``
group.
Seed hypervisor
If provisioning a seed VM, a host should exist for the hypervisor that
will run the VM, and should be a member of the ``seed-hypervisor`` group.
Seed
The seed host, whether provisioned as a VM by Kayobe or externally managed,
should exist in the ``seed`` group.
Cloud hosts and bare metal compute hosts are not required to exist in the
inventory.
Site Localisation and Customisation
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Site localisation and customisation is applied using Ansible extra-vars files
in ``${KAYOBE_CONFIG_PATH}/*.yml``.
Encryption of Secrets
^^^^^^^^^^^^^^^^^^^^^
Kayobe supports the use of `Ansible vault
<http://docs.ansible.com/ansible/playbooks_vault.html>`_ to encrypt sensitive
information in its configuration. The ``ansible-vault`` tool should be used to
manage individual files for which encryption is required. Any of the
configuration files may be encrypted. Since encryption can make working with
Kayobe difficult, it is recommended to follow `best practice
<http://docs.ansible.com/ansible/playbooks_best_practices.html#best-practices-for-variables-and-vaults>`_,
adding a layer of indirection and using encryption only where necessary.
Command Line Interface Command Line Interface
====================== ======================