# -*- coding: utf-8 -*-

#

# Majic Ansible Roles documentation build configuration file, created by

# sphinx-quickstart on Sat Nov  8 14:03:39 2014.

#

# This file is execfile()d with the current directory set to its

# containing dir.

#

# Note that not all possible configuration values are present in this

# autogenerated file.

#

# All configuration values have a default; values that are commented out

# serve to show the default.

import sys

import os

# If extensions (or modules to document with autodoc) are in another directory,

# add these directories to sys.path here. If the directory is relative to the

# documentation root, use os.path.abspath to make it absolute, like shown here.

#sys.path.insert(0, os.path.abspath('.'))

# -- General configuration ------------------------------------------------

# If your documentation needs a minimal Sphinx version, state it here.

#needs_sphinx = '1.0'

# Add any Sphinx extension module names here, as strings. They can be

# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom

# ones.

extensions = []

# Add any paths that contain templates here, relative to this directory.

templates_path = ['_templates']

# The suffix of source filenames.

source_suffix = '.rst'

# The encoding of source files.

#source_encoding = 'utf-8-sig'

# The master toctree document.

master_doc = 'index'

# General information about the project.

project = u'Majic Ansible Roles'

copyright = u'2016, Branko Majic'

# The version info for the project you're documenting, acts as replacement for

# |version| and |release|, also used in various other places throughout the

# built documents.

#

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# for a list of supported languages.

#

# This is also used if you do content translation via gettext catalogs.

# Usually you set "language" from the command line for these cases.

language = None

# There are two options for replacing |today|: either, you set today to some

# non-false value, then it is used:

#today = ''

# Else, today_fmt is used as the format for a strftime call.

#today_fmt = '%B %d, %Y'

# List of patterns, relative to source directory, that match files and

# directories to ignore when looking for source files.

exclude_patterns = ['_build']

# The reST default role (used for this markup: `text`) to use for all

# documents.

#default_role = None

# If true, '()' will be appended to :func: etc. cross-reference text.

#add_function_parentheses = True

# If true, the current module name will be prepended to all description

# unit titles (such as .. function::).

#add_module_names = True

# If true, sectionauthor and moduleauthor directives will be shown in the

# output. They are ignored by default.

#show_authors = False

# The name of the Pygments (syntax highlighting) style to use.

pygments_style = 'sphinx'

# A list of ignored prefixes for module index sorting.

#modindex_common_prefix = []

# If true, keep warnings as "system message" paragraphs in the built documents.

#keep_warnings = False

# -- Options for HTML output ----------------------------------------------

# The theme to use for HTML and HTML Help pages.  See the documentation for

# a list of builtin themes.

html_theme = 'classic'

# Theme options are theme-specific and customize the look and feel of a theme

# further.  For a list of options available for each theme, see the

# documentation.

#html_theme_options = {}

# Add any paths that contain custom themes here, relative to this directory.

#html_theme_path = []

# The name for this set of Sphinx documents.  If None, it defaults to

# "<project> v<release> documentation".

#html_title = None

# A shorter title for the navigation bar.  Default is the same as html_title.

#html_short_title = None

# The name of an image file (relative to this directory) to place at the top

# of the sidebar.

#html_logo = None

# The name of an image file (within the static path) to use as favicon of the

# docs.  This file should be a Windows icon file (.ico) being 16x16 or 32x32

# pixels large.

#html_favicon = None

# Add any paths that contain custom static files (such as style sheets) here,

# relative to this directory. They are copied after the builtin static files,

# so a file named "default.css" will overwrite the builtin "default.css".

html_static_path = ['_static']

# Add any extra paths that contain custom files (such as robots.txt or

# .htaccess) here, relative to this directory. These files are copied

# directly to the root of the documentation.

#html_extra_path = []

# If not '', a 'Last updated on:' timestamp is inserted at every page bottom,

# using the given strftime format.

#html_last_updated_fmt = '%b %d, %Y'

# If true, SmartyPants will be used to convert quotes and dashes to

# typographically correct entities.

#html_use_smartypants = True

# Custom sidebar templates, maps document names to template names.

#html_sidebars = {}

# Additional templates that should be rendered to pages, maps page names to

# template names.

#html_additional_pages = {}

# If false, no module index is generated.

#html_domain_indices = True

# If false, no index is generated.

#html_use_index = True

# If true, the index is split into individual pages for each letter.

#html_split_index = False

# If true, links to the reST sources are added to the pages.

#html_show_sourcelink = True

# If true, "Created using Sphinx" is shown in the HTML footer. Default is True.

#html_show_sphinx = True

# If true, "(C) Copyright ..." is shown in the HTML footer. Default is True.

#html_show_copyright = True

# If true, an OpenSearch description file will be output, and all pages will

# contain a <link> tag referring to it.  The value of this option must be the

# base URL from which the finished HTML is served.

#html_use_opensearch = ''

# This is the file name suffix for HTML files (e.g. ".xhtml").

#html_file_suffix = None

# Language to be used for generating the HTML full-text search index.

# Sphinx supports the following languages:

#   'da', 'de', 'en', 'es', 'fi', 'fr', 'hu', 'it', 'ja'

#   'nl', 'no', 'pt', 'ro', 'ru', 'sv', 'tr'

#html_search_language = 'en'

# A dictionary with options for the search language support, empty by default.

# Now only 'ja' uses this config value

#html_search_options = {'type': 'default'}

# The name of a javascript file (relative to the configuration directory) that

# implements a search results scorer. If empty, the default will be used.

#html_search_scorer = 'scorer.js'

# Output file base name for HTML help builder.

htmlhelp_basename = 'MajicAnsibleRolesdoc'

# -- Options for LaTeX output ---------------------------------------------

latex_elements = {

# The paper size ('letterpaper' or 'a4paper').

#'papersize': 'letterpaper',

# The font size ('10pt', '11pt' or '12pt').

#'pointsize': '10pt',

# Additional stuff for the LaTeX preamble.

#'preamble': '',

# Latex figure (float) alignment

#'figure_align': 'htbp',

}

# Grouping the document tree into LaTeX files. List of tuples

# (source start file, target name, title,

#  author, documentclass [howto, manual, or own class]).

latex_documents = [

  ('index', 'MajicAnsibleRoles.tex', u'Majic Ansible Roles Documentation',

   u'Branko Majic', 'manual'),

]

# The name of an image file (relative to this directory) to place at the top of

# the title page.

#latex_logo = None

# For "manual" documents, if this is true, then toplevel headings are parts,

# not chapters.

#latex_use_parts = False

# If true, show page references after internal links.

#latex_show_pagerefs = False

# If true, show URL addresses after external links.

#latex_show_urls = False

# Documents to append as an appendix to all manuals.

#latex_appendices = []

# If false, no module index is generated.

#latex_domain_indices = True

# -- Options for manual page output ---------------------------------------

# One entry per manual page. List of tuples

# (source start file, name, description, authors, manual section).

man_pages = [

    ('index', 'majicansibleroles', u'Majic Ansible Roles Documentation',

.. _usage:

Usage

=====

Majic Ansible Roles are targeted at sysadmins who wish to deploy services for

their own, small-scale use. This chapter gives a simple tutorial-like set of

instructions for using all of the roles available.

.. contents:: :local:

Overview

--------

There is a number of different roles that can prove useful for setting-up a

small infrastructure of your own.

Some roles are suited for one-off operations during installation, like the

``preseed`` and ``bootstrap``, while some are better suited for periodic runs

for maintaining the users and integrity of the system.

By the end of the instructions you will have the following:

* Ansible server, used for configuring the remaining servers.

* Communications server, providing the LDAP, mail, and XMPP services.

* Web server, providing the web services.

* Backup server, where the backups will be stored at.

Pre-requisites

--------------

For the set-up outlined in this usage guide you'll need the following:

* One server where Ansible will be installed at. Debian Jessie will be installed

  on top of this server. The server will be set-up manually (this is currently

  out of scope for the *Majic Ansible Roles* automated set-up).

* Three servers where the services will be set-up. All servers must be able to

  communicate over network with each-other, the Ansible servers, and with

  Internet. Debian Jessie will be installed on top of this server as part of the

  usage instructions.

* Debian Jessie network install CD.

* All servers should be on the same network.

* IP addresses for all servers should be known.

* Netmask for all servers should be known.

* Gateway for all servers should be known.

In case of the servers listed above, it might be safest to have them as VMs -

this is cheapest thing to do, and simplest (who wants to deal with pesky hardware anyway?).

Usage instructions assume the following:

* Domain used for all servers is ``example.com``. If you wish to use a different

  domain, adjust the instructions accordingly.

* Server hostnames are ``ansible``, ``comms``, ``www``, and ``bak`` (for Ansible

  server, communications server, web server, and backup server, respectively).

Installing the OS on Ansible server

-----------------------------------

Start-off by installing the operating system on the Ansible server:

1. Fire-up the ``ansible`` server, and boot from the network installation CD.

2. Select the **Install** option.

3. Pick **English** as language.

4. Pick the country you are living in (or whatever else you want).

5. Pick the **en_US.UTF-8** locale.

6. Pick the **American English** keymap.

7. Configure the network if necessary.

8. Set the hostname to ``ansible``.

9. Set the domain to ``example.com``.

10. Set the root password.

11. Create a new user. For simplicity, call the user **Ansible user**, with

    username **ansible**.

12. Set-up partitioning in any way you want. You can go for **Guided - use

    entire disk** if you want to keep it simple and are just testing things.

13. Wait until the base system has been installed.

14. Pick whatever Debian archive mirror is closest to you.

15. If you have an HTTP proxy, provide its URL.

16. Pick if you want to participate in package survey or not.

17. Make sure that at least the **standard system utilities** and **SSH server**

    options are selected on task selection screen.

18. Wait for packages to be installed.

19. Install the GRUB boot loader on MBR.

20. Finalise the server install, and remove the installation media from server.

Installing required packages

----------------------------

With the operating system installed, it is necessary to install a couple of

packages, and to prepare the environment a bit on the Ansible server:

1. Install the necessary system packages (using the ``root`` account)::

     apt-get install -y virtualenv virtualenvwrapper git python-pip python-dev libffi-dev libssl-dev

2. Set-up the virtual environment (using the ``ansible`` account):

   .. warning::

      If you are already logged-in as user ``ansible`` in the server, you will

      need to log-out and log-in again in order to be able to use

      ``virtualenvwrapper`` commands!

   ::

     mkdir ~/mysite/

     mkvirtualenv -a ~/mysite/ mysite

     pip install -U pip setuptools

     pip install 'ansible~=2.3.0' dnspython

.. warning::

   The ``dnspython`` package is important since it is used internally via

   ``dig`` lookup plugin.

Cloning the *Majic Ansible Roles*

---------------------------------

With most of the software pieces in place, the only missing thing is the Majic

Ansible Roles:

1. Clone the git repository::

     git clone http://code.majic.rs/majic-ansible-roles ~/majic-ansible-roles

2. Checkout the correct version of the roles::

     cd ~/majic-ansible-roles/

Preparing the basic site configuration

--------------------------------------

Phew... Now that was a bit tedious and boring... But at least you are now ready

to set-up your own site :)

First of all, let's set-up some basic directory structure and configuration:

1. Create Ansible configuration file.

   .. warning::

      Since Ansible 2.x has introduced much stricter controls over security of

      deployed Python scripts, it is recommended (as in this example) to use the

      ``pipelining`` option (which should also improve performance). This is in

      particular necessary in cases where the SSH user connecting to remote

      machine is *not* ``root``, but there are tasks that use ``become`` with

      non-root ``become_user`` (which is the case in Majic Ansible Roles). See

      `official documentation

      <http://docs.ansible.com/ansible/latest/become.html#becoming-an-unprivileged-user>`_

      and other alternatives to this.

   :file:`~/mysite/ansible.cfg`

   ::

     [defaults]

     roles_path=/home/ansible/majic-ansible-roles/roles:/home/ansible/mysite/roles

     force_handlers = True

     retry_files_save_path = /home/ansible/mysite/retry

     inventory = /home/ansible/mysite/hosts

     [ssh_connection]

     pipelining = True

2. Create directory where retry files will be stored at (so they woudln't

   pollute your home directory)::

     mkdir ~/mysite/retry

3. Create the hosts file.

   :file:`~/mysite/hosts`

   ::

     [preseed]

     localhost ansible_connection=local

     [communications]

     comms.example.com

     [web]

     www.example.com

     [backup]

     bak.example.com

4. Create a number of directories for storing playbooks, group variables, SSH

   keys, and GnuPG keyring (we'll get to this later)::

     mkdir ~/mysite/playbooks/

     mkdir ~/mysite/group_vars/

     mkdir ~/mysite/ssh/

     mkdir ~/mysite/gnupg/

5. Before moving ahead, we should also create SSH private/public key pair that

   will be used by Ansible for connecting to destination servers, as well as

   for some roles::

     ssh-keygen -f ~/.ssh/id_rsa -N ''

Preseed files

-------------

The ``preseed`` role is useful for generating Debian preseed files. Preseed

files can be used for automating the Debian installation process.

Preseed files are commonly created on the Ansible host, and then in some way

served to the servers using them during install.

So, let's set this up for start:

1. First of all, create the playbook for generating the preseed files locally.

   :file:`~/mysite/playbooks/preseed.yml`

   ::

      ---

      - hosts: preseed

        roles:

          - preseed

2. And that is about it to be able to actually use this particular role! So

   let's try running it::

     workon mysite && ansible-playbook playbooks/preseed.yml

3. If all went well, you should have the following files created:

   * :file:`~/mysite/preseed_files/comms.example.com.cfg`

   * :file:`~/mysite/preseed_files/www.example.com.cfg`

   * :file:`~/mysite/preseed_files/bak.example.com.cfg`

4. You can have a look at them, but you might notice the settings in the file

   might not be to your liking. In particular, it could be using wrong timezone,

   defaulting to DHCP for network configuration etc. Let's concentrate on making

   the network configuration changes - this is the main thing that will probably

   differ in your environment. Create a new configuration file:

   :file:`~/mysite/group_vars/preseed.yml`

   ::

      ---

      # Set your default (initial) root password.

      preseed_root_password: changeit

      # Use manual network configuration (no DHCP).

      preseed_network_auto: no

      # Set the gateway for all servers.

      preseed_gateway: 10.32.64.1

      # Set the netmask for all servers.

      preseed_netmask: 255.255.255.0

      # Set the DNS for all servers.

      preseed_dns: 10.32.64.1

      # Set the domain for all servers.

      preseed_domain: example.com

      # Set the server-specific options.

      preseed_server_overrides:

        comms.example.com:

          hostname: comms

          ip: 10.32.64.19

        www.example.com:

          hostname: www

          ip: 10.32.64.20

        bak.example.com:

          hostname: bak

          ip: 10.32.64.23

5. Now re-run the preseed playbook::

     workon mysite && ansible-playbook playbooks/preseed.yml

6. The preseed files should have been updated now, and you should have the new

   customised configuration files in the ``preseed_files`` directory. You can

   now use these to install the servers.

Installing the servers with preseed files

-----------------------------------------

You have your preseed files now, so you can go ahead and install the servers

``comms.example.com``, ``www.example.com``, and ``bak.example.com`` using

them with network install CD. Have a look at `Debian

<https://www.debian.org/releases/jessie/amd64/apbs02.html.en>`_ instructions for

more details.

If you need to, you can easily serve the preseed files from the Ansible server

with Python's built-in HTTP server::

  cd ~/mysite/preseed_files/

  python -m SimpleHTTPServer 8000

Bootstrapping servers for Ansible set-up

----------------------------------------

In order to effectively use Ansible, a small initial bootstrap always has to be

done for managed servers. This mainly involves set-up of Ansible users on the

destination machine, and distributing the SSH public keys for authorisation.

When you use the preseed configuration files to deploy a server, you get the

benefit of having the authorized_keys set-up for the root operating system user,

making it easier to bootstrap the machines subsequently via Ansible.

Let's bootstrap our machines now:

1. For start, create a dedicated playbook for the bootstrap process.

   :file:`~/mysite/playbooks/bootstrap.yml`

   ::

      ---

      - hosts: [communications, web, backup]

        remote_user: root