Co-authored-by: Sandra McCann <samccann@redhat.com> Co-authored-by: Rick Elrod <rick@elrod.me>
781 lines
34 KiB
ReStructuredText
781 lines
34 KiB
ReStructuredText
.. _ansible_faq:
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Frequently Asked Questions
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==========================
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Here are some commonly asked questions and their answers.
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.. _collections_transition:
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Where did all the modules go?
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+++++++++++++++++++++++++++++
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In July, 2019, we announced that collections would be the `future of Ansible content delivery <https://www.ansible.com/blog/the-future-of-ansible-content-delivery>`_. A collection is a distribution format for Ansible content that can include playbooks, roles, modules, and plugins. In Ansible 2.9 we added support for collections. In Ansible 2.10 we `extracted most modules from the main ansible/ansible repository <https://access.redhat.com/solutions/5295121>`_ and placed them in :ref:`collections <list_of_collections>`. Collections may be maintained by the Ansible team, by the Ansible community, or by Ansible partners. The `ansible/ansible repository <https://github.com/ansible/ansible>`_ now contains the code for basic features and functions, such as copying module code to managed nodes. This code is also known as ``ansible-base``.
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* To learn more about using collections, see :ref:`collections`.
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* To learn more about developing collections, see :ref:`developing_collections`.
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* To learn more about contributing to existing collections, see the individual collection repository for guidelines, or see :ref:`contributing_maintained_collections` to contribute to one of the Ansible-maintained collections.
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.. _find_my_module:
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Where did this specific module go?
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++++++++++++++++++++++++++++++++++
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IF you are searching for a specific module, you can check the `runtime.yml <https://github.com/ansible/ansible/blob/devel/lib/ansible/config/ansible_builtin_runtime.yml>`_ file, which lists the first destination for each module that we extracted from the main ansible/ansible repository. Some modules have moved again since then. You can also search on `Ansible Galaxy <https://galaxy.ansible.com/>`_ or ask on one of our :ref:`IRC channels <communication_irc>`.
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.. _set_environment:
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How can I set the PATH or any other environment variable for a task or entire play?
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+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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Setting environment variables can be done with the `environment` keyword. It can be used at the task or other levels in the play.
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.. code-block:: yaml
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shell:
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cmd: date
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environment:
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LANG=fr_FR.UTF-8
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.. code-block:: yaml
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hosts: servers
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environment:
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PATH: "{{ ansible_env.PATH }}:/thingy/bin"
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SOME: value
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.. note:: starting in 2.0.1 the setup task from ``gather_facts`` also inherits the environment directive from the play, you might need to use the ``|default`` filter to avoid errors if setting this at play level.
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.. _faq_setting_users_and_ports:
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How do I handle different machines needing different user accounts or ports to log in with?
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+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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Setting inventory variables in the inventory file is the easiest way.
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For instance, suppose these hosts have different usernames and ports:
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.. code-block:: ini
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[webservers]
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asdf.example.com ansible_port=5000 ansible_user=alice
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jkl.example.com ansible_port=5001 ansible_user=bob
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You can also dictate the connection type to be used, if you want:
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.. code-block:: ini
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[testcluster]
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localhost ansible_connection=local
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/path/to/chroot1 ansible_connection=chroot
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foo.example.com ansible_connection=paramiko
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You may also wish to keep these in group variables instead, or file them in a group_vars/<groupname> file.
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See the rest of the documentation for more information about how to organize variables.
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.. _use_ssh:
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How do I get ansible to reuse connections, enable Kerberized SSH, or have Ansible pay attention to my local SSH config file?
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++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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Switch your default connection type in the configuration file to ``ssh``, or use ``-c ssh`` to use
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Native OpenSSH for connections instead of the python paramiko library. In Ansible 1.2.1 and later, ``ssh`` will be used
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by default if OpenSSH is new enough to support ControlPersist as an option.
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Paramiko is great for starting out, but the OpenSSH type offers many advanced options. You will want to run Ansible
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from a machine new enough to support ControlPersist, if you are using this connection type. You can still manage
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older clients. If you are using RHEL 6, CentOS 6, SLES 10 or SLES 11 the version of OpenSSH is still a bit old, so
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consider managing from a Fedora or openSUSE client even though you are managing older nodes, or just use paramiko.
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We keep paramiko as the default as if you are first installing Ansible on these enterprise operating systems, it offers a better experience for new users.
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.. _use_ssh_jump_hosts:
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How do I configure a jump host to access servers that I have no direct access to?
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+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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You can set a ``ProxyCommand`` in the
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``ansible_ssh_common_args`` inventory variable. Any arguments specified in
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this variable are added to the sftp/scp/ssh command line when connecting
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to the relevant host(s). Consider the following inventory group:
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.. code-block:: ini
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[gatewayed]
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foo ansible_host=192.0.2.1
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bar ansible_host=192.0.2.2
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You can create `group_vars/gatewayed.yml` with the following contents::
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ansible_ssh_common_args: '-o ProxyCommand="ssh -W %h:%p -q user@gateway.example.com"'
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Ansible will append these arguments to the command line when trying to
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connect to any hosts in the group ``gatewayed``. (These arguments are used
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in addition to any ``ssh_args`` from ``ansible.cfg``, so you do not need to
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repeat global ``ControlPersist`` settings in ``ansible_ssh_common_args``.)
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Note that ``ssh -W`` is available only with OpenSSH 5.4 or later. With
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older versions, it's necessary to execute ``nc %h:%p`` or some equivalent
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command on the bastion host.
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With earlier versions of Ansible, it was necessary to configure a
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suitable ``ProxyCommand`` for one or more hosts in ``~/.ssh/config``,
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or globally by setting ``ssh_args`` in ``ansible.cfg``.
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.. _ssh_serveraliveinterval:
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How do I get Ansible to notice a dead target in a timely manner?
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++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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You can add ``-o ServerAliveInterval=NumberOfSeconds`` in ``ssh_args`` from ``ansible.cfg``. Without this option,
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SSH and therefore Ansible will wait until the TCP connection times out. Another solution is to add ``ServerAliveInterval``
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into your global SSH configuration. A good value for ``ServerAliveInterval`` is up to you to decide; keep in mind that
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``ServerAliveCountMax=3`` is the SSH default so any value you set will be tripled before terminating the SSH session.
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.. _cloud_provider_performance:
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How do I speed up run of ansible for servers from cloud providers (EC2, openstack,.. )?
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+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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Don't try to manage a fleet of machines of a cloud provider from your laptop.
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Rather connect to a management node inside this cloud provider first and run Ansible from there.
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.. _python_interpreters:
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How do I handle not having a Python interpreter at /usr/bin/python on a remote machine?
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++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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While you can write Ansible modules in any language, most Ansible modules are written in Python,
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including the ones central to letting Ansible work.
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By default, Ansible assumes it can find a :command:`/usr/bin/python` on your remote system that is
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either Python2, version 2.6 or higher or Python3, 3.5 or higher.
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Setting the inventory variable ``ansible_python_interpreter`` on any host will tell Ansible to
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auto-replace the Python interpreter with that value instead. Thus, you can point to any Python you
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want on the system if :command:`/usr/bin/python` on your system does not point to a compatible
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Python interpreter.
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Some platforms may only have Python 3 installed by default. If it is not installed as
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:command:`/usr/bin/python`, you will need to configure the path to the interpreter via
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``ansible_python_interpreter``. Although most core modules will work with Python 3, there may be some
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special purpose ones which do not or you may encounter a bug in an edge case. As a temporary
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workaround you can install Python 2 on the managed host and configure Ansible to use that Python via
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``ansible_python_interpreter``. If there's no mention in the module's documentation that the module
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requires Python 2, you can also report a bug on our `bug tracker
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<https://github.com/ansible/ansible/issues>`_ so that the incompatibility can be fixed in a future release.
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Do not replace the shebang lines of your python modules. Ansible will do this for you automatically at deploy time.
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Also, this works for ANY interpreter, for example ruby: ``ansible_ruby_interpreter``, perl: ``ansible_perl_interpreter``, and so on,
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so you can use this for custom modules written in any scripting language and control the interpreter location.
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Keep in mind that if you put ``env`` in your module shebang line (``#!/usr/bin/env <other>``),
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this facility will be ignored so you will be at the mercy of the remote `$PATH`.
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.. _installation_faqs:
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How do I handle the package dependencies required by Ansible package dependencies during Ansible installation ?
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+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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While installing Ansible, sometimes you may encounter errors such as `No package 'libffi' found` or `fatal error: Python.h: No such file or directory`
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These errors are generally caused by the missing packages, which are dependencies of the packages required by Ansible.
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For example, `libffi` package is dependency of `pynacl` and `paramiko` (Ansible -> paramiko -> pynacl -> libffi).
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In order to solve these kinds of dependency issues, you might need to install required packages using
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the OS native package managers, such as `yum`, `dnf`, or `apt`, or as mentioned in the package installation guide.
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Refer to the documentation of the respective package for such dependencies and their installation methods.
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Common Platform Issues
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++++++++++++++++++++++
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What customer platforms does Red Hat support?
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---------------------------------------------
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A number of them! For a definitive list please see this `Knowledge Base article <https://access.redhat.com/articles/3168091>`_.
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Running in a virtualenv
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-----------------------
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You can install Ansible into a virtualenv on the controller quite simply:
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.. code-block:: shell
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$ virtualenv ansible
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$ source ./ansible/bin/activate
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$ pip install ansible
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If you want to run under Python 3 instead of Python 2 you may want to change that slightly:
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.. code-block:: shell
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$ virtualenv -p python3 ansible
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$ source ./ansible/bin/activate
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$ pip install ansible
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If you need to use any libraries which are not available via pip (for instance, SELinux Python
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bindings on systems such as Red Hat Enterprise Linux or Fedora that have SELinux enabled), then you
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need to install them into the virtualenv. There are two methods:
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* When you create the virtualenv, specify ``--system-site-packages`` to make use of any libraries
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installed in the system's Python:
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.. code-block:: shell
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$ virtualenv ansible --system-site-packages
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* Copy those files in manually from the system. For instance, for SELinux bindings you might do:
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.. code-block:: shell
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$ virtualenv ansible --system-site-packages
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$ cp -r -v /usr/lib64/python3.*/site-packages/selinux/ ./py3-ansible/lib64/python3.*/site-packages/
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$ cp -v /usr/lib64/python3.*/site-packages/*selinux*.so ./py3-ansible/lib64/python3.*/site-packages/
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Running on BSD
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--------------
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.. seealso:: :ref:`working_with_bsd`
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Running on Solaris
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------------------
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By default, Solaris 10 and earlier run a non-POSIX shell which does not correctly expand the default
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tmp directory Ansible uses ( :file:`~/.ansible/tmp`). If you see module failures on Solaris machines, this
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is likely the problem. There are several workarounds:
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* You can set ``remote_tmp`` to a path that will expand correctly with the shell you are using
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(see the plugin documentation for :ref:`C shell<csh_shell>`, :ref:`fish shell<fish_shell>`,
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and :ref:`Powershell<powershell_shell>`). For example, in the ansible config file you can set::
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remote_tmp=$HOME/.ansible/tmp
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In Ansible 2.5 and later, you can also set it per-host in inventory like this::
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solaris1 ansible_remote_tmp=$HOME/.ansible/tmp
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* You can set :ref:`ansible_shell_executable<ansible_shell_executable>` to the path to a POSIX compatible shell. For
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instance, many Solaris hosts have a POSIX shell located at :file:`/usr/xpg4/bin/sh` so you can set
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this in inventory like so::
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solaris1 ansible_shell_executable=/usr/xpg4/bin/sh
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(bash, ksh, and zsh should also be POSIX compatible if you have any of those installed).
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Running on z/OS
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---------------
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There are a few common errors that one might run into when trying to execute Ansible on z/OS as a target.
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* Version 2.7.6 of python for z/OS will not work with Ansible because it represents strings internally as EBCDIC.
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To get around this limitation, download and install a later version of `python for z/OS <https://www.rocketsoftware.com/zos-open-source>`_ (2.7.13 or 3.6.1) that represents strings internally as ASCII. Version 2.7.13 is verified to work.
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* When ``pipelining = False`` in `/etc/ansible/ansible.cfg` then Ansible modules are transferred in binary mode via sftp however execution of python fails with
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.. error::
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SyntaxError: Non-UTF-8 code starting with \'\\x83\' in file /a/user1/.ansible/tmp/ansible-tmp-1548232945.35-274513842609025/AnsiballZ_stat.py on line 1, but no encoding declared; see https://python.org/dev/peps/pep-0263/ for details
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To fix it set ``pipelining = True`` in `/etc/ansible/ansible.cfg`.
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* Python interpret cannot be found in default location ``/usr/bin/python`` on target host.
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.. error::
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/usr/bin/python: EDC5129I No such file or directory
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To fix this set the path to the python installation in your inventory like so::
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zos1 ansible_python_interpreter=/usr/lpp/python/python-2017-04-12-py27/python27/bin/python
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* Start of python fails with ``The module libpython2.7.so was not found.``
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.. error::
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EE3501S The module libpython2.7.so was not found.
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On z/OS, you must execute python from gnu bash. If gnu bash is installed at ``/usr/lpp/bash``, you can fix this in your inventory by specifying an ``ansible_shell_executable``::
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zos1 ansible_shell_executable=/usr/lpp/bash/bin/bash
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Running under fakeroot
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----------------------
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Some issues arise as ``fakeroot`` does not create a full nor POSIX compliant system by default.
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It is known that it will not correctly expand the default tmp directory Ansible uses (:file:`~/.ansible/tmp`).
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If you see module failures, this is likely the problem.
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The simple workaround is to set ``remote_tmp`` to a path that will expand correctly (see documentation of the shell plugin you are using for specifics).
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For example, in the ansible config file (or via environment variable) you can set::
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remote_tmp=$HOME/.ansible/tmp
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.. _use_roles:
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What is the best way to make content reusable/redistributable?
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++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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If you have not done so already, read all about "Roles" in the playbooks documentation. This helps you make playbook content
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self-contained, and works well with things like git submodules for sharing content with others.
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If some of these plugin types look strange to you, see the API documentation for more details about ways Ansible can be extended.
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.. _configuration_file:
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Where does the configuration file live and what can I configure in it?
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++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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See :ref:`intro_configuration`.
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.. _who_would_ever_want_to_disable_cowsay_but_ok_here_is_how:
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How do I disable cowsay?
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++++++++++++++++++++++++
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If cowsay is installed, Ansible takes it upon itself to make your day happier when running playbooks. If you decide
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that you would like to work in a professional cow-free environment, you can either uninstall cowsay, set ``nocows=1``
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in ``ansible.cfg``, or set the :envvar:`ANSIBLE_NOCOWS` environment variable:
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.. code-block:: shell-session
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export ANSIBLE_NOCOWS=1
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.. _browse_facts:
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How do I see a list of all of the ansible\_ variables?
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++++++++++++++++++++++++++++++++++++++++++++++++++++++
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Ansible by default gathers "facts" about the machines under management, and these facts can be accessed in playbooks
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and in templates. To see a list of all of the facts that are available about a machine, you can run the ``setup`` module
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as an ad-hoc action:
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.. code-block:: shell-session
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ansible -m setup hostname
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This will print out a dictionary of all of the facts that are available for that particular host. You might want to pipe
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the output to a pager.This does NOT include inventory variables or internal 'magic' variables. See the next question
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if you need more than just 'facts'.
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.. _browse_inventory_vars:
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How do I see all the inventory variables defined for my host?
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+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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By running the following command, you can see inventory variables for a host:
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.. code-block:: shell-session
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ansible-inventory --list --yaml
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.. _browse_host_vars:
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How do I see all the variables specific to my host?
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+++++++++++++++++++++++++++++++++++++++++++++++++++
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To see all host specific variables, which might include facts and other sources:
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.. code-block:: shell-session
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ansible -m debug -a "var=hostvars['hostname']" localhost
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Unless you are using a fact cache, you normally need to use a play that gathers facts first, for facts included in the task above.
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.. _host_loops:
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How do I loop over a list of hosts in a group, inside of a template?
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++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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A pretty common pattern is to iterate over a list of hosts inside of a host group, perhaps to populate a template configuration
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file with a list of servers. To do this, you can just access the "$groups" dictionary in your template, like this:
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.. code-block:: jinja
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{% for host in groups['db_servers'] %}
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{{ host }}
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{% endfor %}
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If you need to access facts about these hosts, for instance, the IP address of each hostname,
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you need to make sure that the facts have been populated. For example, make sure you have a play that talks to db_servers::
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- hosts: db_servers
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tasks:
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- debug: msg="doesn't matter what you do, just that they were talked to previously."
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Then you can use the facts inside your template, like this:
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.. code-block:: jinja
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{% for host in groups['db_servers'] %}
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{{ hostvars[host]['ansible_eth0']['ipv4']['address'] }}
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{% endfor %}
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.. _programatic_access_to_a_variable:
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How do I access a variable name programmatically?
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+++++++++++++++++++++++++++++++++++++++++++++++++
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An example may come up where we need to get the ipv4 address of an arbitrary interface, where the interface to be used may be supplied
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via a role parameter or other input. Variable names can be built by adding strings together, like so:
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.. code-block:: jinja
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{{ hostvars[inventory_hostname]['ansible_' + which_interface]['ipv4']['address'] }}
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The trick about going through hostvars is necessary because it's a dictionary of the entire namespace of variables. ``inventory_hostname``
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is a magic variable that indicates the current host you are looping over in the host loop.
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In the example above, if your interface names have dashes, you must replace them with underscores:
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.. code-block:: jinja
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{{ hostvars[inventory_hostname]['ansible_' + which_interface | replace('_', '-') ]['ipv4']['address'] }}
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Also see dynamic_variables_.
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.. _access_group_variable:
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How do I access a group variable?
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+++++++++++++++++++++++++++++++++
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Technically, you don't, Ansible does not really use groups directly. Groups are labels for host selection and a way to bulk assign variables,
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they are not a first class entity, Ansible only cares about Hosts and Tasks.
|
|
|
|
That said, you could just access the variable by selecting a host that is part of that group, see first_host_in_a_group_ below for an example.
|
|
|
|
|
|
.. _first_host_in_a_group:
|
|
|
|
How do I access a variable of the first host in a group?
|
|
++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
What happens if we want the ip address of the first webserver in the webservers group? Well, we can do that too. Note that if we
|
|
are using dynamic inventory, which host is the 'first' may not be consistent, so you wouldn't want to do this unless your inventory
|
|
is static and predictable. (If you are using :ref:`ansible_tower`, it will use database order, so this isn't a problem even if you are using cloud
|
|
based inventory scripts).
|
|
|
|
Anyway, here's the trick:
|
|
|
|
.. code-block:: jinja
|
|
|
|
{{ hostvars[groups['webservers'][0]]['ansible_eth0']['ipv4']['address'] }}
|
|
|
|
Notice how we're pulling out the hostname of the first machine of the webservers group. If you are doing this in a template, you
|
|
could use the Jinja2 '#set' directive to simplify this, or in a playbook, you could also use set_fact::
|
|
|
|
- set_fact: headnode={{ groups['webservers'][0] }}
|
|
|
|
- debug: msg={{ hostvars[headnode].ansible_eth0.ipv4.address }}
|
|
|
|
Notice how we interchanged the bracket syntax for dots -- that can be done anywhere.
|
|
|
|
.. _file_recursion:
|
|
|
|
How do I copy files recursively onto a target host?
|
|
+++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
The ``copy`` module has a recursive parameter. However, take a look at the ``synchronize`` module if you want to do something more efficient
|
|
for a large number of files. The ``synchronize`` module wraps rsync. See the module index for info on both of these modules.
|
|
|
|
.. _shell_env:
|
|
|
|
How do I access shell environment variables?
|
|
++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
|
|
**On controller machine :** Access existing variables from controller use the ``env`` lookup plugin.
|
|
For example, to access the value of the HOME environment variable on the management machine::
|
|
|
|
---
|
|
# ...
|
|
vars:
|
|
local_home: "{{ lookup('env','HOME') }}"
|
|
|
|
|
|
**On target machines :** Environment variables are available via facts in the ``ansible_env`` variable:
|
|
|
|
.. code-block:: jinja
|
|
|
|
{{ ansible_env.HOME }}
|
|
|
|
If you need to set environment variables for TASK execution, see :ref:`playbooks_environment`
|
|
in the :ref:`Advanced Playbooks <playbooks_special_topics>` section.
|
|
There are several ways to set environment variables on your target machines. You can use the
|
|
:ref:`template <template_module>`, :ref:`replace <replace_module>`, or :ref:`lineinfile <lineinfile_module>`
|
|
modules to introduce environment variables into files. The exact files to edit vary depending on your OS
|
|
and distribution and local configuration.
|
|
|
|
.. _user_passwords:
|
|
|
|
How do I generate encrypted passwords for the user module?
|
|
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
Ansible ad-hoc command is the easiest option:
|
|
|
|
.. code-block:: shell-session
|
|
|
|
ansible all -i localhost, -m debug -a "msg={{ 'mypassword' | password_hash('sha512', 'mysecretsalt') }}"
|
|
|
|
The ``mkpasswd`` utility that is available on most Linux systems is also a great option:
|
|
|
|
.. code-block:: shell-session
|
|
|
|
mkpasswd --method=sha-512
|
|
|
|
|
|
If this utility is not installed on your system (for example, you are using macOS) then you can still easily
|
|
generate these passwords using Python. First, ensure that the `Passlib <https://foss.heptapod.net/python-libs/passlib/-/wikis/home>`_
|
|
password hashing library is installed:
|
|
|
|
.. code-block:: shell-session
|
|
|
|
pip install passlib
|
|
|
|
Once the library is ready, SHA512 password values can then be generated as follows:
|
|
|
|
.. code-block:: shell-session
|
|
|
|
python -c "from passlib.hash import sha512_crypt; import getpass; print(sha512_crypt.using(rounds=5000).hash(getpass.getpass()))"
|
|
|
|
Use the integrated :ref:`hash_filters` to generate a hashed version of a password.
|
|
You shouldn't put plaintext passwords in your playbook or host_vars; instead, use :ref:`playbooks_vault` to encrypt sensitive data.
|
|
|
|
In OpenBSD, a similar option is available in the base system called ``encrypt (1)``
|
|
|
|
.. _dot_or_array_notation:
|
|
|
|
Ansible allows dot notation and array notation for variables. Which notation should I use?
|
|
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
The dot notation comes from Jinja and works fine for variables without special
|
|
characters. If your variable contains dots (.), colons (:), or dashes (-), if
|
|
a key begins and ends with two underscores, or if a key uses any of the known
|
|
public attributes, it is safer to use the array notation. See :ref:`playbooks_variables`
|
|
for a list of the known public attributes.
|
|
|
|
.. code-block:: jinja
|
|
|
|
item[0]['checksum:md5']
|
|
item['section']['2.1']
|
|
item['region']['Mid-Atlantic']
|
|
It is {{ temperature['Celsius']['-3'] }} outside.
|
|
|
|
Also array notation allows for dynamic variable composition, see dynamic_variables_.
|
|
|
|
Another problem with 'dot notation' is that some keys can cause problems because they collide with attributes and methods of python dictionaries.
|
|
|
|
.. code-block:: jinja
|
|
|
|
item.update # this breaks if item is a dictionary, as 'update()' is a python method for dictionaries
|
|
item['update'] # this works
|
|
|
|
|
|
.. _argsplat_unsafe:
|
|
|
|
When is it unsafe to bulk-set task arguments from a variable?
|
|
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
|
|
You can set all of a task's arguments from a dictionary-typed variable. This
|
|
technique can be useful in some dynamic execution scenarios. However, it
|
|
introduces a security risk. We do not recommend it, so Ansible issues a
|
|
warning when you do something like this::
|
|
|
|
#...
|
|
vars:
|
|
usermod_args:
|
|
name: testuser
|
|
state: present
|
|
update_password: always
|
|
tasks:
|
|
- user: '{{ usermod_args }}'
|
|
|
|
This particular example is safe. However, constructing tasks like this is
|
|
risky because the parameters and values passed to ``usermod_args`` could
|
|
be overwritten by malicious values in the ``host facts`` on a compromised
|
|
target machine. To mitigate this risk:
|
|
|
|
* set bulk variables at a level of precedence greater than ``host facts`` in the order of precedence
|
|
found in :ref:`ansible_variable_precedence` (the example above is safe because play vars take
|
|
precedence over facts)
|
|
* disable the :ref:`inject_facts_as_vars` configuration setting to prevent fact values from colliding
|
|
with variables (this will also disable the original warning)
|
|
|
|
|
|
.. _commercial_support:
|
|
|
|
Can I get training on Ansible?
|
|
++++++++++++++++++++++++++++++
|
|
|
|
Yes! See our `services page <https://www.ansible.com/products/consulting>`_ for information on our services
|
|
and training offerings. Email `info@ansible.com <mailto:info@ansible.com>`_ for further details.
|
|
|
|
We also offer free web-based training classes on a regular basis. See our
|
|
`webinar page <https://www.ansible.com/resources/webinars-training>`_ for more info on upcoming webinars.
|
|
|
|
|
|
.. _web_interface:
|
|
|
|
Is there a web interface / REST API / GUI?
|
|
++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
Yes! Ansible, Inc makes a great product that makes Ansible even more powerful and easy to use. See :ref:`ansible_tower`.
|
|
|
|
|
|
.. _keep_secret_data:
|
|
|
|
How do I keep secret data in my playbook?
|
|
+++++++++++++++++++++++++++++++++++++++++
|
|
|
|
If you would like to keep secret data in your Ansible content and still share it publicly or keep things in source control, see :ref:`playbooks_vault`.
|
|
|
|
If you have a task that you don't want to show the results or command given to it when using -v (verbose) mode, the following task or playbook attribute can be useful::
|
|
|
|
- name: secret task
|
|
shell: /usr/bin/do_something --value={{ secret_value }}
|
|
no_log: True
|
|
|
|
This can be used to keep verbose output but hide sensitive information from others who would otherwise like to be able to see the output.
|
|
|
|
The ``no_log`` attribute can also apply to an entire play::
|
|
|
|
- hosts: all
|
|
no_log: True
|
|
|
|
Though this will make the play somewhat difficult to debug. It's recommended that this
|
|
be applied to single tasks only, once a playbook is completed. Note that the use of the
|
|
``no_log`` attribute does not prevent data from being shown when debugging Ansible itself via
|
|
the :envvar:`ANSIBLE_DEBUG` environment variable.
|
|
|
|
|
|
.. _when_to_use_brackets:
|
|
.. _dynamic_variables:
|
|
.. _interpolate_variables:
|
|
|
|
When should I use {{ }}? Also, how to interpolate variables or dynamic variable names
|
|
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
A steadfast rule is 'always use ``{{ }}`` except when ``when:``'.
|
|
Conditionals are always run through Jinja2 as to resolve the expression,
|
|
so ``when:``, ``failed_when:`` and ``changed_when:`` are always templated and you should avoid adding ``{{ }}``.
|
|
|
|
In most other cases you should always use the brackets, even if previously you could use variables without
|
|
specifying (like ``loop`` or ``with_`` clauses), as this made it hard to distinguish between an undefined variable and a string.
|
|
|
|
Another rule is 'moustaches don't stack'. We often see this:
|
|
|
|
.. code-block:: jinja
|
|
|
|
{{ somevar_{{other_var}} }}
|
|
|
|
The above DOES NOT WORK as you expect, if you need to use a dynamic variable use the following as appropriate:
|
|
|
|
.. code-block:: jinja
|
|
|
|
{{ hostvars[inventory_hostname]['somevar_' + other_var] }}
|
|
|
|
For 'non host vars' you can use the :ref:`vars lookup<vars_lookup>` plugin:
|
|
|
|
.. code-block:: jinja
|
|
|
|
{{ lookup('vars', 'somevar_' + other_var) }}
|
|
|
|
|
|
.. _why_no_wheel:
|
|
|
|
Why don't you ship ansible in wheel format (or other packaging format) ?
|
|
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
In most cases it has to do with maintainability. There are many ways to ship software and we do not have
|
|
the resources to release Ansible on every platform.
|
|
In some cases there are technical issues. For example, our dependencies are not present on Python Wheels.
|
|
|
|
.. _ansible_host_delegated:
|
|
|
|
How do I get the original ansible_host when I delegate a task?
|
|
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
As the documentation states, connection variables are taken from the ``delegate_to`` host so ``ansible_host`` is overwritten,
|
|
but you can still access the original via ``hostvars``::
|
|
|
|
original_host: "{{ hostvars[inventory_hostname]['ansible_host'] }}"
|
|
|
|
This works for all overridden connection variables, like ``ansible_user``, ``ansible_port``, and so on.
|
|
|
|
|
|
.. _scp_protocol_error_filename:
|
|
|
|
How do I fix 'protocol error: filename does not match request' when fetching a file?
|
|
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
Since release ``7.9p1`` of OpenSSH there is a `bug <https://bugzilla.mindrot.org/show_bug.cgi?id=2966>`_
|
|
in the SCP client that can trigger this error on the Ansible controller when using SCP as the file transfer mechanism::
|
|
|
|
failed to transfer file to /tmp/ansible/file.txt\r\nprotocol error: filename does not match request
|
|
|
|
In these releases, SCP tries to validate that the path of the file to fetch matches the requested path.
|
|
The validation
|
|
fails if the remote filename requires quotes to escape spaces or non-ascii characters in its path. To avoid this error:
|
|
|
|
* Use SFTP instead of SCP by setting ``scp_if_ssh`` to ``smart`` (which tries SFTP first) or to ``False``. You can do this in one of four ways:
|
|
* Rely on the default setting, which is ``smart`` - this works if ``scp_if_ssh`` is not explicitly set anywhere
|
|
* Set a :ref:`host variable <host_variables>` or :ref:`group variable <group_variables>` in inventory: ``ansible_scp_if_ssh: False``
|
|
* Set an environment variable on your control node: ``export ANSIBLE_SCP_IF_SSH=False``
|
|
* Pass an environment variable when you run Ansible: ``ANSIBLE_SCP_IF_SSH=smart ansible-playbook``
|
|
* Modify your ``ansible.cfg`` file: add ``scp_if_ssh=False`` to the ``[ssh_connection]`` section
|
|
* If you must use SCP, set the ``-T`` arg to tell the SCP client to ignore path validation. You can do this in one of three ways:
|
|
* Set a :ref:`host variable <host_variables>` or :ref:`group variable <group_variables>`: ``ansible_scp_extra_args=-T``,
|
|
* Export or pass an environment variable: ``ANSIBLE_SCP_EXTRA_ARGS=-T``
|
|
* Modify your ``ansible.cfg`` file: add ``scp_extra_args=-T`` to the ``[ssh_connection]`` section
|
|
|
|
.. note:: If you see an ``invalid argument`` error when using ``-T``, then your SCP client is not performing filename validation and will not trigger this error.
|
|
|
|
.. _mfa_support:
|
|
|
|
Does Ansible support multiple factor authentication 2FA/MFA/biometrics/finterprint/usbkey/OTP/...
|
|
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
No, Ansible is designed to execute multiple tasks against multiple targets, minimizing user interaction.
|
|
As with most automation tools, it is not compatible with interactive security systems designed to handle human interaction.
|
|
Most of these systems require a secondary prompt per target, which prevents scaling to thousands of targets. They also
|
|
tend to have very short expiration periods so it requires frequent reauthorization, also an issue with many hosts and/or
|
|
a long set of tasks.
|
|
|
|
In such environments we recommend securing around Ansible's execution but still allowing it to use an 'automation user' that does not require such measures.
|
|
This is something that Tower/AWX excels at by allowing administrators to set up RBAC access to inventory, along with managing credentials and job execution.
|
|
|
|
|
|
.. _docs_contributions:
|
|
|
|
How do I submit a change to the documentation?
|
|
++++++++++++++++++++++++++++++++++++++++++++++
|
|
|
|
Documentation for Ansible is kept in the main project git repository, and complete instructions
|
|
for contributing can be found in the docs README `viewable on GitHub <https://github.com/ansible/ansible/blob/devel/docs/docsite/README.md>`_. Thanks!
|
|
|
|
.. _i_dont_see_my_question:
|
|
|
|
I don't see my question here
|
|
++++++++++++++++++++++++++++
|
|
|
|
Please see the section below for a link to IRC and the Google Group, where you can ask your question there.
|
|
|
|
.. seealso::
|
|
|
|
:ref:`working_with_playbooks`
|
|
An introduction to playbooks
|
|
:ref:`playbooks_best_practices`
|
|
Tips and tricks for playbooks
|
|
`User Mailing List <https://groups.google.com/group/ansible-project>`_
|
|
Have a question? Stop by the google group!
|
|
`irc.freenode.net <http://irc.freenode.net>`_
|
|
#ansible IRC chat channel
|