Ansible 2.8 Porting Guide

This section discusses the behavioral changes between Ansible 2.7 and Ansible 2.8.

It is intended to assist in updating your playbooks, plugins and other parts of your Ansible infrastructure so they will work with this version of Ansible.

We suggest you read this page along with Ansible Changelog for 2.8 to understand what updates you may need to make.

This document is part of a collection on porting. The complete list of porting guides can be found at porting guides.

Playbook

Distribution Facts

The information returned for the ansible_distribution_* group of facts may have changed slightly. Ansible 2.8 uses a new backend library for information about distributions: nir0s/distro. This library runs on Python-3.8 and fixes many bugs, including correcting release and version names.

The two facts used in playbooks most often, ansible_distribution and ansible_distribution_major_version, should not change. If you discover a change in these facts, please file a bug so we can address the difference. However, other facts like ansible_distribution_release and ansible_distribution_version may change as erroneous information gets corrected.

Imports as handlers

Beginning in version 2.8, a task cannot notify import_tasks or a static include that is specified in handlers.

The goal of a static import is to act as a pre-processor, where the import is replaced by the tasks defined within the imported file. When using an import, a task can notify any of the named tasks within the imported file, but not the name of the import itself.

To achieve the results of notifying a single name but running multiple handlers, utilize include_tasks, or listen Handlers: running operations on change.

Jinja Undefined values

Beginning in version 2.8, attempting to access an attribute of an Undefined value in Jinja will return another Undefined value, rather than throwing an error immediately. This means that you can now simply use a default with a value in a nested data structure when you don’t know if the intermediate values are defined.

In Ansible 2.8:

{{ foo.bar.baz | default('DEFAULT') }}

In Ansible 2.7 and older:

{{ ((foo | default({})).bar | default({})).baz | default('DEFAULT') }}

or:

{{ foo.bar.baz if (foo is defined and foo.bar is defined and foo.bar.baz is defined) else 'DEFAULT' }}

Module option conversion to string

Beginning in version 2.8, Ansible will warn if a module expects a string, but a non-string value is passed and automatically converted to a string. This highlights potential problems where, for example, a yes or true (parsed as truish boolean value) would be converted to the string 'True', or where a version number 1.10 (parsed as float value) would be converted to '1.1'. Such conversions can result in unexpected behavior depending on context.

This behavior can be changed to be an error or to be ignored by setting the ANSIBLE_STRING_CONVERSION_ACTION environment variable, or by setting the string_conversion_action configuration in the defaults section of ansible.cfg.

Command line facts

cmdline facts returned in system will be deprecated in favor of proc_cmdline. This change handles special case where Kernel command line parameter contains multiple values with the same key.

Bare variables in conditionals

In Ansible 2.7 and earlier, top-level variables sometimes treated boolean strings as if they were boolean values. This led to inconsistent behavior in conditional tests built on top-level variables defined as strings. Ansible 2.8 began changing this behavior. For example, if you set two conditions like this:

tasks:
  - include_tasks: teardown.yml
    when: teardown

  - include_tasks: provision.yml
    when: not teardown

based on a variable you define as a string (with quotation marks around it):

  • In Ansible 2.7 and earlier, the two conditions above evaluated as True and False respectively if teardown: 'true'

  • In Ansible 2.7 and earlier, both conditions evaluated as False if teardown: 'false'

  • In Ansible 2.8 and later, you have the option of disabling conditional bare variables, so when: teardown always evaluates as True and when: not teardown always evaluates as False when teardown is a non-empty string (including 'true' or 'false')

Ultimately, when: 'string' will always evaluate as True and when: not 'string' will always evaluate as False, as long as 'string' is not empty, even if the value of 'string' itself looks like a boolean. For users with playbooks that depend on the old behavior, we added a config setting that preserves it. You can use the ANSIBLE_CONDITIONAL_BARE_VARS environment variable or conditional_bare_variables in the defaults section of ansible.cfg to select the behavior you want on your control node. The default setting is true, which preserves the old behavior. Set the config value or environment variable to false to start using the new option.

Note

In 2.10 the default setting for conditional_bare_variables will change to false. In 2.12 the old behavior will be deprecated.

Updating your playbooks

To prepare your playbooks for the new behavior, you must update your conditional statements so they accept only boolean values. For variables, you can use the bool filter to evaluate the string 'false' as False:

vars:
  teardown: 'false'

tasks:
  - include_tasks: teardown.yml
    when: teardown | bool

  - include_tasks: provision.yml
    when: not teardown | bool

Alternatively, you can re-define your variables as boolean values (without quotation marks) instead of strings:

vars:
  teardown: false

tasks:
  - include_tasks: teardown.yml
    when: teardown

  - include_tasks: provision.yml
    when: not teardown

For dictionaries and lists, use the length filter to evaluate the presence of a dictionary or list as True:

- debug:
  when: my_list | length > 0

- debug:
  when: my_dictionary | length > 0

Do not use the bool filter with lists or dictionaries. If you use bool with a list or dict, Ansible will always evaluate it as False.

Double-interpolation

The conditional_bare_variables setting also affects variables set based on other variables. The old behavior unexpectedly double-interpolated those variables. For example:

vars:
  double_interpolated: 'bare_variable'
  bare_variable: false

tasks:
  - debug:
    when: double_interpolated

  • In Ansible 2.7 and earlier, when: double_interpolated evaluated to the value of bare_variable, in this case, False. If the variable bare_variable is undefined, the conditional fails.

  • In Ansible 2.8 and later, with bare variables disabled, Ansible evaluates double_interpolated as the string 'bare_variable', which is True.

To double-interpolate variable values, use curly braces:

vars:
  double_interpolated: "{{ other_variable }}"
  other_variable: false

Nested variables

The conditional_bare_variables setting does not affect nested variables. Any string value assigned to a subkey is already respected and not treated as a boolean. If complex_variable['subkey'] is a non-empty string, then when: complex_variable['subkey'] is always True and when: not complex_variable['subkey'] is always False. If you want a string subkey like complex_variable['subkey'] to be evaluated as a boolean, you must use the bool filter.

Gathering Facts

In Ansible 2.8 the implicit “Gathering Facts” task in a play was changed to obey play tags. Previous to 2.8, the “Gathering Facts” task would ignore play tags and tags supplied from the command line and always run in a task.

The behavior change affects the following example play.

- name: Configure Webservers
  hosts: webserver
  tags:
    - webserver
  tasks:
    - name: Install nginx
      package:
        name: nginx
      tags:
        - nginx

In Ansible 2.8, if you supply --tags nginx, the implicit “Gathering Facts” task will be skipped, as the task now inherits the tag of webserver instead of always.

If no play level tags are set, the “Gathering Facts” task will be given a tag of always and will effectively match prior behavior.

You can achieve similar results to the pre-2.8 behavior, by using an explicit gather_facts task in your tasks list.

- name: Configure Webservers
  hosts: webserver
  gather_facts: false
  tags:
    - webserver
  tasks:
    - name: Gathering Facts
      gather_facts:
      tags:
        - always

    - name: Install nginx
      package:
        name: nginx
      tags:
        - nginx

Python Interpreter Discovery

In Ansible 2.7 and earlier, Ansible defaulted to /usr/bin/python as the setting for ansible_python_interpreter. If you ran Ansible against a system that installed Python with a different name or a different path, your playbooks would fail with /usr/bin/python: bad interpreter: No such file or directory unless you either set ansible_python_interpreter to the correct value for that system or added a Python interpreter and any necessary dependencies at usr/bin/python.

Starting in Ansible 2.8, Ansible searches for the correct path and executable name for Python on each target system, first in a lookup table of default Python interpreters for common distros, then in an ordered fallback list of possible Python interpreter names/paths.

It’s risky to rely on a Python interpreter set from the fallback list, because the interpreter may change on future runs. If an interpreter from higher in the fallback list gets installed (for example, as a side-effect of installing other packages), your original interpreter and its dependencies will no longer be used. For this reason, Ansible warns you when it uses a Python interpreter discovered from the fallback list. If you see this warning, the best solution is to explicitly set ansible_python_interpreter to the path of the correct interpreter for those target systems.

You can still set ansible_python_interpreter to a specific path at any variable level (as a host variable, in vars files, in playbooks, and so on). If you prefer to use the Python interpreter discovery behavior, use one of the four new values for ansible_python_interpreter introduced in Ansible 2.8:

New value

Behavior

auto
(future default)

If a Python interpreter is discovered, Ansible uses the discovered Python, even if /usr/bin/python is also present. Warns when using the fallback list.

auto_legacy
(Ansible 2.8 default)

If a Python interpreter is discovered, and /usr/bin/python is absent, Ansible uses the discovered Python. Warns when using the fallback list.

If a Python interpreter is discovered, and /usr/bin/python is present, Ansible uses /usr/bin/python and prints a deprecation warning about future default behavior. Warns when using the fallback list.

auto_legacy_silent

Behaves like auto_legacy but suppresses the deprecation and fallback-list warnings.

auto_silent

Behaves like auto but suppresses the fallback-list warning.

In Ansible 2.12, Ansible will switch the default from auto_legacy to auto. The difference in behaviour is that auto_legacy uses /usr/bin/python if present and falls back to the discovered Python when it is not present. auto will always use the discovered Python, regardless of whether /usr/bin/python exists. The auto_legacy setting provides compatibility with previous versions of Ansible that always defaulted to /usr/bin/python.

If you installed Python and dependencies (boto, and so on) to /usr/bin/python as a workaround on distros with a different default Python interpreter (for example, Ubuntu 16.04+, RHEL8, Fedora 23+), you have two options:

  1. Move existing dependencies over to the default Python for each platform/distribution/version.

  2. Use auto_legacy. This setting lets Ansible find and use the workaround Python on hosts that have it, while also finding the correct default Python on newer hosts. But remember, the default will change in 4 releases.

Retry File Creation default

In Ansible 2.8, retry_files_enabled now defaults to False instead of True. The behavior can be modified to previous version by editing the default ansible.cfg file and setting the value to True.

Command Line

Become Prompting

Beginning in version 2.8, by default Ansible will use the word BECOME to prompt you for a password for elevated privileges (sudo privileges on Unix systems or enable mode on network devices):

By default in Ansible 2.8:

ansible-playbook --become --ask-become-pass site.yml
BECOME password:

If you want the prompt to display the specific become_method you’re using, instead of the general value BECOME, set AGNOSTIC_BECOME_PROMPT to False in your Ansible configuration.

By default in Ansible 2.7, or with AGNOSTIC_BECOME_PROMPT=False in Ansible 2.8:

ansible-playbook --become --ask-become-pass site.yml
SUDO password:

Deprecated

  • Setting the async directory using ANSIBLE_ASYNC_DIR as an task/play environment key is deprecated and will be removed in Ansible 2.12. You can achieve the same result by setting ansible_async_dir as a variable like:

    - name: run task with custom async directory
  command: sleep 5
  async: 10
  vars:
    ansible_async_dir: /tmp/.ansible_async

  • Plugin writers who need a FactCache object should be aware of two deprecations:

    1. The FactCache class has moved from ansible.plugins.cache.FactCache to ansible.vars.fact_cache.FactCache. This is because the FactCache is not part of the cache plugin API and cache plugin authors should not be subclassing it. FactCache is still available from its old location but will issue a deprecation warning when used from there. The old location will be removed in Ansible 2.12.

    2. The FactCache.update() method has been converted to follow the dict API. It now takes a dictionary as its sole argument and updates itself with the dictionary’s items. The previous API where update() took a key and a value will now issue a deprecation warning and will be removed in 2.12. If you need the old behavior switch to FactCache.first_order_merge() instead.

  • Supporting file-backed caching through self.cache is deprecated and will be removed in Ansible 2.12. If you maintain an inventory plugin, update it to use self._cache as a dictionary. For implementation details, see the developer guide on inventory plugins.

  • Importing cache plugins directly is deprecated and will be removed in Ansible 2.12. Use the plugin_loader so direct options, environment variables, and other means of configuration can be reconciled using the config system rather than constants.

    from ansible.plugins.loader import cache_loader
cache = cache_loader.get('redis', **kwargs)

Modules

Major changes in popular modules are detailed here

The exec wrapper that runs PowerShell modules has been changed to set $ErrorActionPreference = "Stop" globally. This may mean that custom modules can fail if they implicitly relied on this behavior. To get the old behavior back, add $ErrorActionPreference = "Continue" to the top of the module. This change was made to restore the old behavior of the EAP that was accidentally removed in a previous release and ensure that modules are more resilient to errors that may occur in execution.

  • Version 2.8.14 of Ansible changed the default mode of file-based tasks to 0o600 & ~umask when the user did not specify a mode parameter on file-based tasks. This was in response to a CVE report which we have reconsidered. As a result, the mode change has been reverted in 2.8.15, and mode will now default to 0o666 & ~umask as in previous versions of Ansible.

  • If you changed any tasks to specify less restrictive permissions while using 2.8.14, those changes will be unnecessary (but will do no harm) in 2.8.15.

  • To avoid the issue raised in CVE-2020-1736, specify a mode parameter in all file-based tasks that accept it.

  • dnf and yum - As of version 2.8.15, the dnf module (and yum action when it uses dnf) now correctly validates GPG signatures of packages (CVE-2020-14365). If you see an error such as Failed to validate GPG signature for [package name], please ensure that you have imported the correct GPG key for the DNF repository and/or package you are using. One way to do this is with the rpm_key module. Although we discourage it, in some cases it may be necessary to disable the GPG check. This can be done by explicitly adding disable_gpg_check: yes in your dnf or yum task.

Modules removed

The following modules no longer exist:

  • ec2_remote_facts

  • azure

  • cs_nic

  • netscaler

  • win_msi

Deprecation notices

The following modules will be removed in Ansible 2.12. Please update your playbooks accordingly.

  • foreman use foreman-ansible-modules instead.

  • katello use foreman-ansible-modules instead.

  • github_hooks use github_webhook and github_webhook_facts instead.

  • digital_ocean use digital_ocean_droplet instead.

  • gce use gcp_compute_instance instead.

  • gcspanner use gcp_spanner_instance and gcp_spanner_database instead.

  • gcdns_record use gcp_dns_resource_record_set instead.

  • gcdns_zone use gcp_dns_managed_zone instead.

  • gcp_forwarding_rule use gcp_compute_global_forwarding_rule or gcp_compute_forwarding_rule instead.

  • gcp_healthcheck use gcp_compute_health_check, gcp_compute_http_health_check, or gcp_compute_https_health_check instead.

  • gcp_backend_service use gcp_compute_backend_service instead.

  • gcp_target_proxy use gcp_compute_target_http_proxy instead.

  • gcp_url_map use gcp_compute_url_map instead.

  • panos use the Palo Alto Networks Ansible Galaxy role instead.

Noteworthy module changes

  • The foreman and katello modules have been deprecated in favor of a set of modules that are broken out per entity with better idempotency in mind.

  • The foreman and katello modules replacement is officially part of the Foreman Community and supported there.

  • The tower_credential module originally required the ssh_key_data to be the path to a ssh_key_file. In order to work like AWX/Tower/RHAAP, ssh_key_data now contains the content of the file. The previous behavior can be achieved with lookup('file', '/path/to/file').

  • The win_scheduled_task module deprecated support for specifying a trigger repetition as a list and this format will be removed in Ansible 2.12. Instead specify the repetition as a dictionary value.

  • The win_feature module has removed the deprecated restart_needed return value, use the standardized reboot_required value instead.

  • The win_package module has removed the deprecated restart_required and exit_code return value, use the standardized reboot_required and rc value instead.

  • The win_get_url module has removed the deprecated win_get_url return dictionary, contained values are returned directly.

  • The win_get_url module has removed the deprecated skip_certificate_validation option, use the standardized validate_certs option instead.

  • The vmware_local_role_facts module now returns a list of dicts instead of a dict of dicts for role information.

  • If docker_network or docker_volume were called with diff: yes, check_mode: yes or debug: yes, a return value called diff was returned of type list. To enable proper diff output, this was changed to type dict; the original list is returned as diff.differences.

  • The na_ontap_cluster_peer module has replaced source_intercluster_lif and dest_intercluster_lif string options with source_intercluster_lifs and dest_intercluster_lifs list options

  • The modprobe module now detects kernel builtins. Previously, attempting to remove (with state: absent) a builtin kernel module succeeded without any error message because modprobe did not detect the module as present. Now, modprobe will fail if a kernel module is builtin and state: absent (with an error message from the modprobe binary like modprobe: ERROR: Module nfs is builtin.), and it will succeed without reporting changed if state: present. Any playbooks that are using changed_when: no to mask this quirk can safely remove that workaround. To get the previous behavior when applying state: absent to a builtin kernel module, use failed_when: false or ignore_errors: true in your playbook.

  • The digital_ocean module has been deprecated in favor of modules that do not require external dependencies. This allows for more flexibility and better module support.

  • The docker_container module has deprecated the returned fact docker_container. The same value is available as the returned variable container. The returned fact will be removed in Ansible 2.12.

  • The docker_network module has deprecated the returned fact docker_container. The same value is available as the returned variable network. The returned fact will be removed in Ansible 2.12.

  • The docker_volume module has deprecated the returned fact docker_container. The same value is available as the returned variable volume. The returned fact will be removed in Ansible 2.12.

  • The docker_service module was renamed to docker_compose.

  • The renamed docker_compose module used to return one fact per service, named same as the service. A dictionary of these facts is returned as the regular return value services. The returned facts will be removed in Ansible 2.12.

  • The docker_swarm_service module no longer sets a defaults for the following options:

    • user. Before, the default was root.

    • update_delay. Before, the default was 10.

    • update_parallelism. Before, the default was 1.

  • vmware_vm_facts used to return dict of dict with virtual machine’s facts. Ansible 2.8 and onwards will return list of dict with virtual machine’s facts. Please see module vmware_vm_facts documentation for example.

  • vmware_guest_snapshot module used to return results. Since Ansible 2.8 and onwards results is a reserved keyword, it is replaced by snapshot_results. Please see module vmware_guest_snapshots documentation for example.

  • The panos modules have been deprecated in favor of using the Palo Alto Networks Ansible Galaxy role. Contributions to the role can be made here.

  • The ipa_user module originally always sent password to FreeIPA regardless of whether the password changed. Now the module only sends password if update_password is set to always, which is the default.

  • The win_psexec has deprecated the undocumented extra_opts module option. This will be removed in Ansible 2.10.

  • The win_nssm module has deprecated the following options in favor of using the win_service module to configure the service after installing it with win_nssm: * dependencies, use dependencies of win_service instead * start_mode, use start_mode of win_service instead * user, use username of win_service instead * password, use password of win_service instead These options will be removed in Ansible 2.12.

  • The win_nssm module has also deprecated the start, stop, and restart values of the status option. You should use the win_service module to control the running state of the service. This will be removed in Ansible 2.12.

  • The status module option for win_nssm has changed its default value to present. Before, the default was start. Consequently, the service is no longer started by default after creation with win_nssm, and you should use the win_service module to start it if needed.

  • The app_parameters module option for win_nssm has been deprecated; use argument instead. This will be removed in Ansible 2.12.

  • The app_parameters_free_form module option for win_nssm has been aliased to the new arguments option.

  • The win_dsc module will now validate the input options for a DSC resource. In previous versions invalid options would be ignored but are now not.

  • The openssl_pkcs12 module will now regenerate the pkcs12 file if there are differences between the file on disk and the parameters passed to the module.

Plugins

  • Ansible no longer defaults to the paramiko connection plugin when using macOS as the control node. Ansible will now use the ssh connection plugin by default on a macOS control node. Since ssh supports connection persistence between tasks and playbook runs, it performs better than paramiko. If you are using password authentication, you will need to install sshpass when using the ssh connection plugin. Or you can explicitly set the connection type to paramiko to maintain the pre-2.8 behavior on macOS.

  • Connection plugins have been standardized to allow use of ansible_<conn-type>_user and ansible_<conn-type>_password variables. Variables such as ansible_<conn-type>_pass and ansible_<conn-type>_username are treated with lower priority than the standardized names and may be deprecated in the future. In general, the ansible_user and ansible_password vars should be used unless there is a reason to use the connection-specific variables.

  • The powershell shell plugin now uses async_dir to define the async path for the results file and the default has changed to %USERPROFILE%\.ansible_async. To control this path now, either set the ansible_async_dir variable or the async_dir value in the powershell section of the config ini.

  • Order of enabled inventory plugins (INVENTORY_ENABLED) has been updated, auto is now before yaml and ini.

  • The private _options attribute has been removed from the CallbackBase class of callback plugins. If you have a third-party callback plugin which needs to access the command line arguments, use code like the following instead of trying to use self._options:

    from ansible import context
[...]
tags = context.CLIARGS['tags']

    context.CLIARGS is a read-only dictionary so normal dictionary retrieval methods like CLIARGS.get('tags') and CLIARGS['tags'] work as expected but you won’t be able to modify the cli arguments at all.

  • Play recap now counts ignored and rescued tasks as well as ok, changed, unreachable, failed and skipped tasks, thanks to two additional stat counters in the default callback plugin. Tasks that fail and have ignore_errors: yes set are listed as ignored. Tasks that fail and then execute a rescue section are listed as rescued. Note that rescued tasks are no longer counted as failed as in Ansible 2.7 (and earlier).

  • osx_say callback plugin was renamed into say.

  • Inventory plugins now support caching through cache plugins. To start using a cache plugin with your inventory see the section on caching in the inventory guide. To port a custom cache plugin to be compatible with inventory see developer guide on cache plugins.

Porting custom scripts

Display class

As of Ansible 2.8, the Display class is now a “singleton”. Instead of using __main__.display each file should import and instantiate ansible.utils.display.Display on its own.

OLD In Ansible 2.7 (and earlier) the following was used to access the display object:

try:
    from __main__ import display
except ImportError:
    from ansible.utils.display import Display
    display = Display()

NEW In Ansible 2.8 the following should be used:

from ansible.utils.display import Display
display = Display()

Networking

  • The eos_config, ios_config, and nxos_config modules have removed the deprecated save and force parameters, use the save_when parameter to replicate their functionality.

  • The nxos_vrf_af module has removed the safi parameter. This parameter was deprecated in Ansible 2.4 and has had no impact on the module since then.