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diff --git a/docs/docsite/rst/os_guide/intro_bsd.rst b/docs/docsite/rst/os_guide/intro_bsd.rst new file mode 100644 index 0000000..6e92b2a --- /dev/null +++ b/docs/docsite/rst/os_guide/intro_bsd.rst @@ -0,0 +1,278 @@ +.. _working_with_bsd: + +Managing BSD hosts with Ansible +=============================== + +Managing BSD machines is different from managing other Unix-like machines. If you have managed nodes running BSD, review these topics. + +.. contents:: + :local: + +Connecting to BSD nodes +----------------------- + +Ansible connects to managed nodes using OpenSSH by default. This works on BSD if you use SSH keys for authentication. However, if you use SSH passwords for authentication, Ansible relies on sshpass. Most +versions of sshpass do not deal well with BSD login prompts, so when using SSH passwords against BSD machines, use ``paramiko`` to connect instead of OpenSSH. You can do this in ansible.cfg globally or you can set it as an inventory/group/host variable. For example: + +.. code-block:: text + + [freebsd] + mybsdhost1 ansible_connection=paramiko + +.. _bootstrap_bsd: + +Bootstrapping BSD +----------------- + +Ansible is agentless by default, however, it requires Python on managed nodes. Only the :ref:`raw <raw_module>` module will operate without Python. Although this module can be used to bootstrap Ansible and install Python on BSD variants (see below), it is very limited and the use of Python is required to make full use of Ansible's features. + +The following example installs Python which includes the json library required for full functionality of Ansible. +On your control machine you can execute the following for most versions of FreeBSD: + +.. code-block:: bash + + ansible -m raw -a "pkg install -y python" mybsdhost1 + +Or for OpenBSD: + +.. code-block:: bash + + ansible -m raw -a "pkg_add python%3.8" + +Once this is done you can now use other Ansible modules apart from the ``raw`` module. + +.. note:: + This example demonstrated using pkg on FreeBSD and pkg_add on OpenBSD, however you should be able to substitute the appropriate package tool for your BSD; the package name may also differ. Refer to the package list or documentation of the BSD variant you are using for the exact Python package name you intend to install. + +.. BSD_python_location: + +Setting the Python interpreter +------------------------------ + +To support a variety of Unix-like operating systems and distributions, Ansible cannot always rely on the existing environment or ``env`` variables to locate the correct Python binary. By default, modules point at ``/usr/bin/python`` as this is the most common location. On BSD variants, this path may differ, so it is advised to inform Ansible of the binary's location. See :ref:`INTERPRETER_PYTHON`. For example, set ``ansible_python_interpreter`` inventory variable: + +.. code-block:: ini + + [freebsd:vars] + ansible_python_interpreter=/usr/local/bin/python + [openbsd:vars] + ansible_python_interpreter=/usr/local/bin/python3.8 + + +FreeBSD packages and ports +"""""""""""""""""""""""""" + +In FreeBSD, there is no guarantee that either ``/usr/local/bin/python`` executable file or a link to an executable file is installed by default. The best practice for a remote host, with respect to Ansible, is to install at least the Python version supported by Ansible, for example, ``lang/python38``, and both meta ports ``lang/python3`` and ``lang/python``. Quoting from */usr/ports/lang/python3/pkg-descr*: + +.. code-block:: text + + This is a meta port to the Python 3.x interpreter and provides symbolic links + to bin/python3, bin/pydoc3, bin/idle3 and so on to allow compatibility with + minor version agnostic python scripts. + +Quoting from */usr/ports/lang/python/pkg-descr*: + +.. code-block:: text + + This is a meta port to the Python interpreter and provides symbolic links + to bin/python, bin/pydoc, bin/idle and so on to allow compatibility with + version agnostic python scripts. + +As a result, the following packages are installed: + +.. code-block:: text + + shell> pkg info | grep python + python-3.8_3,2 "meta-port" for the default version of Python interpreter + python3-3_3 Meta-port for the Python interpreter 3.x + python38-3.8.12_1 Interpreted object-oriented programming language + +and the following executables and links + +.. code-block:: text + + shell> ll /usr/local/bin/ | grep python + lrwxr-xr-x 1 root wheel 7 Jan 24 08:30 python@ -> python3 + lrwxr-xr-x 1 root wheel 14 Jan 24 08:30 python-config@ -> python3-config + lrwxr-xr-x 1 root wheel 9 Jan 24 08:29 python3@ -> python3.8 + lrwxr-xr-x 1 root wheel 16 Jan 24 08:29 python3-config@ -> python3.8-config + -r-xr-xr-x 1 root wheel 5248 Jan 13 01:12 python3.8* + -r-xr-xr-x 1 root wheel 3153 Jan 13 01:12 python3.8-config* + + +INTERPRETER_PYTHON_FALLBACK +""""""""""""""""""""""""""" + +Since version 2.8 Ansible provides a useful variable ``ansible_interpreter_python_fallback`` to specify a list of paths to search for Python. See :ref:`INTERPRETER_PYTHON_FALLBACK`. This list will be searched and the first item found will be used. For example, the configuration below would make the installation of the meta-ports in the previous section redundant, that is, if you don't install the Python meta ports the first two items in the list will be skipped and ``/usr/local/bin/python3.8`` will be discovered. + +.. code-block:: ini + + ansible_interpreter_python_fallback=['/usr/local/bin/python', '/usr/local/bin/python3', '/usr/local/bin/python3.8'] + + +You can use this variable, prolonged by the lower versions of Python, and put it, for example, into the ``group_vars/all``. Then, override it for specific groups in ``group_vars/{group1, group2, ...}`` and for specific hosts in ``host_vars/{host1, host2, ...}`` if needed. See :ref:`ansible_variable_precedence`. + + +Debug the discovery of Python +""""""""""""""""""""""""""""" + +For example, given the inventory + +.. code-block:: ini + + shell> cat hosts + [test] + test_11 + test_12 + test_13 + + [test:vars] + ansible_connection=ssh + ansible_user=admin + ansible_become=true + ansible_become_user=root + ansible_become_method=sudo + ansible_interpreter_python_fallback=['/usr/local/bin/python', '/usr/local/bin/python3', '/usr/local/bin/python3.8'] + ansible_perl_interpreter=/usr/local/bin/perl + +The playbook below + +.. code-block:: yaml+jinja + + shell> cat playbook.yml + - hosts: test_11 + gather_facts: false + tasks: + - command: which python + register: result + - debug: + var: result.stdout + - debug: + msg: |- + {% for i in _vars %} + {{ i }}: + {{ lookup('vars', i)|to_nice_yaml|indent(2) }} + {% endfor %} + vars: + _vars: "{{ query('varnames', '.*python.*') }}" + +displays the details + +.. code-block:: yaml + + shell> ansible-playbook -i hosts playbook.yml + + PLAY [test_11] ******************************************************************************* + + TASK [command] ******************************************************************************* + [WARNING]: Platform freebsd on host test_11 is using the discovered Python interpreter at + /usr/local/bin/python, but future installation of another Python interpreter could change the + meaning of that path. See https://docs.ansible.com/ansible- + core/2.12/reference_appendices/interpreter_discovery.html for more information. + changed: [test_11] + + TASK [debug] ********************************************************************************* + ok: [test_11] => + result.stdout: /usr/local/bin/python + + TASK [debug] ********************************************************************************* + ok: [test_11] => + msg: |- + ansible_interpreter_python_fallback: + - /usr/local/bin/python + - /usr/local/bin/python3 + - /usr/local/bin/python3.8 + + discovered_interpreter_python: + /usr/local/bin/python + + ansible_playbook_python: + /usr/bin/python3 + +You can see that the first item from the list ``ansible_interpreter_python_fallback`` was discovered at the FreeBSD remote host. The variable ``ansible_playbook_python`` keeps the path to Python at the Linux controller that ran the playbook. + +Regarding the warning, quoting from :ref:`INTERPRETER_PYTHON` + +.. code-block:: text + + The fallback behavior will issue a warning that the interpreter + should be set explicitly (since interpreters installed later may + change which one is used). This warning behavior can be disabled by + setting auto_silent or auto_legacy_silent. ... + +You can either ignore it or get rid of it by setting the variable ``ansible_python_interpreter=auto_silent`` because this is, actually, what you want by using ``/usr/local/bin/python`` (*"interpreters installed later may change which one is used"*). For example + +.. code-block:: ini + + shell> cat hosts + [test] + test_11 + test_12 + test_13 + + [test:vars] + ansible_connection=ssh + ansible_user=admin + ansible_become=true + ansible_become_user=root + ansible_become_method=sudo + ansible_interpreter_python_fallback=['/usr/local/bin/python', '/usr/local/bin/python3', '/usr/local/bin/python3.8'] + ansible_python_interpreter=auto_silent + ansible_perl_interpreter=/usr/local/bin/perl + + +.. seealso:: + + * :ref:`interpreter_discovery` + * `FreeBSD Wiki: Ports/DEFAULT_VERSIONS <https://wiki.freebsd.org/Ports/DEFAULT_VERSIONS>`_ + + +Additional variables +"""""""""""""""""""" + +If you use additional plugins beyond those bundled with Ansible, you can set similar variables for ``bash``, ``perl`` or ``ruby``, depending on how the plugin is written. For example: + +.. code-block:: ini + + [freebsd:vars] + ansible_python_interpreter=/usr/local/bin/python + ansible_perl_interpreter=/usr/local/bin/perl + + +Which modules are available? +---------------------------- + +The majority of the core Ansible modules are written for a combination of Unix-like machines and other generic services, so most should function well on the BSDs with the obvious exception of those that are aimed at Linux-only technologies (such as LVG). + +Using BSD as the control node +----------------------------- + +Using BSD as the control machine is as simple as installing the Ansible package for your BSD variant or by following the ``pip`` or 'from source' instructions. + +.. _bsd_facts: + +BSD facts +--------- + +Ansible gathers facts from the BSDs in a similar manner to Linux machines, but since the data, names and structures can vary for network, disks and other devices, one should expect the output to be slightly different yet still familiar to a BSD administrator. + +.. _bsd_contributions: + +BSD efforts and contributions +----------------------------- + +BSD support is important to us at Ansible. Even though the majority of our contributors use and target Linux we have an active BSD community and strive to be as BSD-friendly as possible. +Please feel free to report any issues or incompatibilities you discover with BSD; pull requests with an included fix are also welcome! + +.. seealso:: + + :ref:`intro_adhoc` + Examples of basic commands + :ref:`working_with_playbooks` + Learning ansible's configuration management language + :ref:`developing_modules` + How to write modules + `Mailing List <https://groups.google.com/group/ansible-project>`_ + Questions? Help? Ideas? Stop by the list on Google Groups + :ref:`communication_irc` + How to join Ansible chat channels |