Ansible Cheat Sheet
An Ansible summary
Jon Warbrick, July 2014, V3.2 (for Ansible 1.7)
Configuration file
First one found from of
- Contents of $ANSIBLE_CONFIG
- ./ansible.cfg
- ~/.ansible.cfg
- /etc/ansible/ansible.cfg
Configuration settings can be overridden by environment variables - see constants.py in the source tree for names.
Patterns
Used on the ansible command line, or in playbooks.
- all (or *)
- hostname: foo.example.com
- groupname: webservers
- or: webservers:dbserver
- exclude: webserver:!phoenix
- intersection: webservers:&staging
Operators can be chained: webservers:dbservers:&staging:!phoenix
Patterns can include variable substitutions: {{foo}}, wildcards: *.example.com or 192.168.1.*, and regular expressions: ~(web|db).*\.example\.com
Inventory files
intro_inventory.html, intro_dynamic_inventory.html
'INI-file' structure, blocks define groups. Hosts allowed in more than one group. Non-standard SSH port can follow hostname separated by ':' (but see also ansible_ssh_port below).
Hostname ranges: www[01:50].example.com, db-[a:f].example.com
Per-host variables: foo.example.com foo=bar baz=wibble
- [foo:children]: new group foo containing all members if included groups
- [foo:vars]: variable definitions for all members of group foo
Inventory file defaults to /etc/ansible/hosts. Veritable with -i or in the configuration file. The 'file' can also be a dynamic inventory script. If a directory, all contained files are processed.
Variable files:
YAML; given inventory file at ./hosts:
- ./group_vars/foo: variable definitions for all members of group foo
- ./host_vars/foo.example.com: variable definitions for foo.example.com
group_vars and host_vars directories can also exist in the playbook directory. If both paths exist, variables in the playbook directory will be loaded second.
Behavioral inventory parameters:
- ansible_ssh_host
- ansible_ssh_port
- ansible_ssh_user
- ansible_ssh_pass
- ansible_sudo_pass
- ansible_connection
- ansible_ssh_private_key_file
- ansible_python_interpreter
- ansible_*_interpreter
Playbooks
playbooks_intro.html, playbooks_roles.html
Playbooks are a YAML list of one or more plays. Most (all?) keys are optional. Lines can be broken on space with continuation lines indented.
Playbooks consist of a list of one or more 'plays' and/or inclusions:
--- - include: playbook.yml - <play> - ...
Plays
playbooks_intro.html, playbooks_roles.html, playbooks_variables.html, playbooks_conditionals.html,playbooks_acceleration.html, playbooks_delegation.html, playbooks_prompts.html, playbooks_tags.html Forum postingForum postinb
Plays consist of play metadata and a sequence of task and handler definitions, and roles.
- hosts: webservers
remote_user: root
sudo: yes
sudo_user: postgress
su: yes
su_user: exim
gather_facts: no
accelerate: no
accelerate_port: 5099
any_errors_fatal: yes
max_fail_percentage: 30
connection: local
serial: 5
vars:
http_port: 80
vars_files:
- "vars.yml"
- [ "try-first.yml", "try-second-.yml" ]
vars_prompt:
- name: "my_password2"
prompt: "Enter password2"
default: "secret"
private: yes
encrypt: "md5_crypt"
confirm: yes
salt: 1234
salt_size: 8
tags:
- stuff
- nonsence
pre_tasks:
- <task>
- ...
roles:
- common
- { role: common, port: 5000, when: "bar == 'Baz'", tags :[one, two] }
- { role: common, when: month == 'Jan' }
- ...
tasks:
- include: tasks.yaml
- include: tasks.yaml foo=bar baz=wibble
- include: tasks.yaml
vars:
foo: aaa
baz:
- z
- y
- { include: tasks.yaml, foo: zzz, baz: [a,b]}
- include: tasks.yaml
when: day == 'Thursday'
- <task>
- ...
post_tasks:
- <task>
- ...
handlers:
- include: handlers.yml
- <task>
- ...
Using encrypt with vars_prompt requires that Passlib is installed.
In addition the source code implies the availability of the following which don't seem to be mentioned in the documentation: name, user (deprecated), port, accelerate_ipv6, role_names, and vault_password.
Task definitions
playbooks_intro.html, playbooks_roles.html, playbooks_async.html, playbooks_checkmode.html, playbooks_delegation.html,playbooks_environment.html, playbooks_error_handling.html, playbooks_tags.html ansible-1-5-released Forum postingAnsible examples
Each task definition is a list of items, normally including at least a name and a module invocation:
- name: task
remote_user: apache
sudo: yes
sudo_user: postgress
sudo_pass: wibble
su: yes
su_user: exim
ignore_errors: True
delegate_to: 127.0.0.1
async: 45
poll: 5
always_run: no
run_once: false
meta: flush_handlers
no_log: true
environment: <hash>
environment:
var1: val1
var2: val2
tags:
- stuff
- nonsence
<module>: src=template.j2 dest=/etc/foo.conf
action: <module>, src=template.j2 dest=/etc/foo.conf
action: <module>
args:
src=template.j2
dest=/etc/foo.conf
local_action: <module> /usr/bin/take_out_of_pool {{ inventory_hostname }}
when: ansible_os_family == "Debian"
register: result
failed_when: "'FAILED' in result.stderr"
changed_when: result.rc != 2
notify:
- restart apache
delegate_to: 127.0.0.1 is implied by local_action:
The forms <module>: <args>, action: <module> <args>, and local_action: <module> <args> are mutually-exclusive.
Additional keys when_*, until, retries and delay are documented below under 'Loops'.
In addition the source code implies the availability of the following which don't seem to be mentioned in the documentation:first_available_file (deprecated), transport, connection, any_errors_fatal.
Roles
Directory structure:
playbook.yml
roles/
common/
tasks/
main.yml
handlers/
main.yml
vars/
main.yml
meta/
main.yml
defaults/
main.yml
files/
templates/
library/
Modules
modules.htm, modules_by_category.html
List all installed modules with
ansible-doc --list
Document a particular module with
ansible-doc <module>
Show playbook snippet for specified module
ansible-doc -i <module>
Variables
playbooks_roles.html, playbooks_variables.html
Names: letters, digits, underscores; starting with a letter.
Substitution examples:
- {{ var }}
- {{ var["key1"]["key2"]}}
- {{ var.key1.key2 }}
- {{ list[0] }}
YAML requires an item starting with a variable substitution to be quoted.
Sources:
- Highest priority:
- --extra-vars on the command line
- General:
- vars component of a playbook
- From files referenced by vars_file in a playbook
- From included files (incl. roles)
- Parameters passed to includes
- register: in tasks
- Lower priority:
- Inventory (set on host or group)
- Lower priority:
- Facts (see below)
- Any /etc/ansible/facts.d/filename.fact on managed machines (sets variables with `ansible_local.filename. prefix)
- Lowest priority
- Role defaults (from defaults/main.yml)
Built-in:
- hostvars (e.g. hostvars[other.example.com][...])
- group_names (groups containing current host)
- groups (all groups and hosts in the inventory)
- inventory_hostname (current host as in inventory)
- inventory_hostname_short (first component of inventory_hostname)
- play_hosts (hostnames in scope for current play)
- inventory_dir (location of the inventory)
- inventoty_file (name of the inventory)
Facts:
Run ansible hostname -m setup, but in particular:
- ansible_distribution
- ansible_distribution_release
- ansible_distribution_version
- ansible_fqdn
- ansible_hostname
- ansible_os_family
- ansible_pkg_mgr
- ansible_default_ipv4.address
- ansible_default_ipv6.address
Content of 'registered' variables:
playbooks_conditionals.html, playbooks_loops.html
Depends on module. Typically includes:
- .rc
- .stdout
- .stdout_lines
- .changed
- .msg (following failure)
- .results (when used in a loop)
See also failed, changed, etc filters.
When used in a loop the result element is a list containing all responses from the module.
Additionally available in templates:
- ansible_managed: string containing the information below
- template_host: node name of the template�s machine
- template_uid: the owner
- template_path: absolute path of the template
- template_fullpath: the absolute path of the template
- template_run_date: the date that the template was rendered
Filters
- {{ var | to_nice_json }}
- {{ var | to_json }}
- {{ var | from_json }}
- {{ var | to_nice_yml }}
- {{ var | to_yml }}
- {{ var | from_yml }}
- {{ result | failed }}
- {{ result | changed }}
- {{ result | success }}
- {{ result | skipped }}
- {{ var | manditory }}
- {{ var | default(5) }}
- {{ list1 | unique }}
- {{ list1 | union(list2) }}
- {{ list1 | intersect(list2) }}
- {{ list1 | difference(list2) }}
- {{ list1 | symmetric_difference(list2) }}
- {{ ver1 | version_compare(ver2, operator='>=', strict=True }}
- {{ list | random }}
- {{ number | random }}
- {{ number | random(start=1, step=10) }}
- {{ list | join(" ") }}
- {{ path | basename }}
- {{ path | dirname }}
- {{ path | expanduser }}
- {{ path | realpath }}
- {{ var | b64decode }}
- {{ var | b64encode }}
- {{ filename | md5 }}
- {{ var | bool }}
- {{ var | int }}
- {{ var | quote }}
- {{ var | md5 }}
- {{ var | fileglob }}
- {{ var | match }}
- {{ var | search }}
- {{ var | regex }}
- {{ var | regexp_replace('from', 'to' )}}
See also default jinja2 filters. In YAML, values starting { must be quoted.
Lookups
Lookups are evaluated on the control machine.
- {{ lookup('file', '/etc/foo.txt') }}
- {{ lookup('password', '/tmp/passwordfile length=20 chars=ascii_letters,digits') }}
- {{ lookup('env','HOME') }}
- {{ lookup('pipe','date') }}
- {{ lookup('redis_kv', 'redis://localhost:6379,somekey') }}
- {{ lookup('dnstxt', 'example.com') }}
- {{ lookup('template', './some_template.j2') }}
Lookups can be assigned to variables and will be evaluated each time the variable is used.
Lookup plugins also support loop iteration (see below).
Conditions
when: <condition>, where condition is:
- var == "Vaue", var >= 5, etc.
- var, where var coreces to boolean (yes, true, True, TRUE)
- var is defined, var is not defined
- <condition1> and <condition2> (also or?)
Combined with with_items, the when statement is processed for each item.
when can also be applied to includes and roles. Conditional Imports and variable substitution in file and template names can avoid the need for explicit conditionals.
Loops
In addition the source code implies the availability of the following which don't seem to be mentioned in the documentation: csvfile, etcd, inventory_hostname.
Standard:
- user: name={{ item }} state=present groups=wheel
with_items:
- testuser1
- testuser2
- name: add several users
user: name={{ item.name }} state=present groups={{ item.groups }}
with_items:
- { name: 'testuser1', groups: 'wheel' }
- { name: 'testuser2', groups: 'root' }
with_items: somelist
Nested:
- mysql_user: name={{ item[0] }} priv={{ item[1] }}.*:ALL
append_privs=yes password=foo
with_nested:
- [ 'alice', 'bob', 'eve' ]
- [ 'clientdb', 'employeedb', 'providerdb' ]
Over hashes:
Given
---
users:
alice:
name: Alice Appleworth
telephone: 123-456-7890
bob:
name: Bob Bananarama
telephone: 987-654-3210
tasks:
- name: Print phone records
debug: msg="User {{ item.key }} is {{ item.value.name }}
({{ item.value.telephone }})"
with_dict: users
Fileglob:
- copy: src={{ item }} dest=/etc/fooapp/ owner=root mode=600
with_fileglob:
- /playbooks/files/fooapp/*
In a role, relative paths resolve relative to the roles/<rolename>/files directory.
With content of file:
(see example for authorized_key module)
- authorized_key: user=deploy key="{{ item }}"
with_file:
- public_keys/doe-jane
- public_keys/doe-john
See also the file lookup when the content of a file is needed.
Parallel sets of data:
Given
---
alpha: [ 'a', 'b', 'c', 'd' ]
numbers: [ 1, 2, 3, 4 ]
- debug: msg="{{ item.0 }} and {{ item.1 }}"
with_together:
- alpha
- numbers
Subelements:
Given
---
users:
- name: alice
authorized:
- /tmp/alice/onekey.pub
- /tmp/alice/twokey.pub
- name: bob
authorized:
- /tmp/bob/id_rsa.pub
- authorized_key: "user={{ item.0.name }}
key='{{ lookup('file', item.1) }}'"
with_subelements:
- users
- authorized
Integer sequence:
Decimal, hexadecimal (0x3f8) or octal (0600)
- user: name={{ item }} state=present groups=evens
with_sequence: start=0 end=32 format=testuser%02x
with_sequence: start=4 end=16 stride=2
with_sequence: count=4
Random choice:
- debug: msg={{ item }}
with_random_choice:
- "go through the door"
- "drink from the goblet"
- "press the red button"
- "do nothing"
Do-Until:
- action: shell /usr/bin/foo
register: result
until: result.stdout.find("all systems go") != -1
retries: 5
delay: 10
Results of a local program:
- name: Example of looping over a command result
shell: /usr/bin/frobnicate {{ item }}
with_lines: /usr/bin/frobnications_per_host
--param {{ inventory_hostname }}
To loop over the results of a remote program, use register: result and then with_items: result.stdout_lines in a subsequent task.
Indexed list:
- name: indexed loop demo
debug: msg="at array position {{ item.0 }} there is
a value {{ item.1 }}"
with_indexed_items: some_list
Flattened list:
---
# file: roles/foo/vars/main.yml
packages_base:
- [ 'foo-package', 'bar-package' ]
packages_apps:
- [ ['one-package', 'two-package' ]]
- [ ['red-package'], ['blue-package']]
- name: flattened loop demo
yum: name={{ item }} state=installed
with_flattened:
- packages_base
- packages_apps
First found:
- name: template a file
template: src={{ item }} dest=/etc/myapp/foo.conf
with_first_found:
- files:
- {{ ansible_distribution }}.conf
- default.conf
paths:
- search_location_one/somedir/
- /opt/other_location/somedir/
Tags
Both plays and tasks support a tags: attribute.
- template: src=templates/src.j2 dest=/etc/foo.conf
tags:
- configuration
Tags can be applied to roles and includes (effectively tagging all included tasks)
roles:
- { role: webserver, port: 5000, tags: [ 'web', 'foo' ] }
- include: foo.yml tags=web,foo
To select by tag:
ansible-playbook example.yml --tags "configuration,packages" ansible-playbook example.yml --skip-tags "notification"
Command lines
ansible
Usage: ansible <host-pattern> [options]
Options:
-a MODULE_ARGS, --args=MODULE_ARGS
module arguments
-k, --ask-pass ask for SSH password
--ask-su-pass ask for su password
-K, --ask-sudo-pass ask for sudo password
--ask-vault-pass ask for vault password
-B SECONDS, --background=SECONDS
run asynchronously, failing after X seconds
(default=N/A)
-C, --check don't make any changes; instead, try to predict some
of the changes that may occur
-c CONNECTION, --connection=CONNECTION
connection type to use (default=smart)
-f FORKS, --forks=FORKS
specify number of parallel processes to use
(default=5)
-h, --help show this help message and exit
-i INVENTORY, --inventory-file=INVENTORY
specify inventory host file
(default=/etc/ansible/hosts)
-l SUBSET, --limit=SUBSET
further limit selected hosts to an additional pattern
--list-hosts outputs a list of matching hosts; does not execute
anything else
-m MODULE_NAME, --module-name=MODULE_NAME
module name to execute (default=command)
-M MODULE_PATH, --module-path=MODULE_PATH
specify path(s) to module library
(default=/usr/share/ansible)
-o, --one-line condense output
-P POLL_INTERVAL, --poll=POLL_INTERVAL
set the poll interval if using -B (default=15)
--private-key=PRIVATE_KEY_FILE
use this file to authenticate the connection
-S, --su run operations with su
-R SU_USER, --su-user=SU_USER
run operations with su as this user (default=root)
-s, --sudo run operations with sudo (nopasswd)
-U SUDO_USER, --sudo-user=SUDO_USER
desired sudo user (default=root)
-T TIMEOUT, --timeout=TIMEOUT
override the SSH timeout in seconds (default=10)
-t TREE, --tree=TREE log output to this directory
-u REMOTE_USER, --user=REMOTE_USER
connect as this user (default=jw35)
--vault-password-file=VAULT_PASSWORD_FILE
vault password file
-v, --verbose verbose mode (-vvv for more, -vvvv to enable
connection debugging)
--version show program's version number and exit
ansible-playbook
Usage: ansible-playbook playbook.yml
Options:
-k, --ask-pass ask for SSH password
--ask-su-pass ask for su password
-K, --ask-sudo-pass ask for sudo password
--ask-vault-pass ask for vault password
-C, --check don't make any changes; instead, try to predict some
of the changes that may occur
-c CONNECTION, --connection=CONNECTION
connection type to use (default=smart)
-D, --diff when changing (small) files and templates, show the
differences in those files; works great with --check
-e EXTRA_VARS, --extra-vars=EXTRA_VARS
set additional variables as key=value or YAML/JSON
-f FORKS, --forks=FORKS
specify number of parallel processes to use
(default=5)
-h, --help show this help message and exit
-i INVENTORY, --inventory-file=INVENTORY
specify inventory host file
(default=/etc/ansible/hosts)
-l SUBSET, --limit=SUBSET
further limit selected hosts to an additional pattern
--list-hosts outputs a list of matching hosts; does not execute
anything else
--list-tasks list all tasks that would be executed
-M MODULE_PATH, --module-path=MODULE_PATH
specify path(s) to module library
(default=/usr/share/ansible)
--private-key=PRIVATE_KEY_FILE
use this file to authenticate the connection
--skip-tags=SKIP_TAGS
only run plays and tasks whose tags do not match these
values
--start-at-task=START_AT
start the playbook at the task matching this name
--step one-step-at-a-time: confirm each task before running
-S, --su run operations with su
-R SU_USER, --su-user=SU_USER
run operations with su as this user (default=root)
-s, --sudo run operations with sudo (nopasswd)
-U SUDO_USER, --sudo-user=SUDO_USER
desired sudo user (default=root)
--syntax-check perform a syntax check on the playbook, but do not
execute it
-t TAGS, --tags=TAGS only run plays and tasks tagged with these values
-T TIMEOUT, --timeout=TIMEOUT
override the SSH timeout in seconds (default=10)
-u REMOTE_USER, --user=REMOTE_USER
connect as this user (default=jw35)
--vault-password-file=VAULT_PASSWORD_FILE
vault password file
-v, --verbose verbose mode (-vvv for more, -vvvv to enable
connection debugging)
--version show program's version number and exit
ansible-vault
playbooks_vault.html
Usage: ansible-vault [create|decrypt|edit|encrypt|rekey] [--help] [options] file_name Options: -h, --help show this help message and exit See 'ansible-vault <command> --help' for more information on a specific command.
ansible-doc
Usage: ansible-doc [options] [module...]
Show Ansible module documentation
Options:
--version show program's version number and exit
-h, --help show this help message and exit
-M MODULE_PATH, --module-path=MODULE_PATH
Ansible modules/ directory
-l, --list List available modules
-s, --snippet Show playbook snippet for specified module(s)
-v Show version number and exit
ansible-galaxy
Usage: ansible-galaxy [init|info|install|list|remove] [--help] [options] ... Options: -h, --help show this help message and exit See 'ansible-galaxy <command> --help' for more information on a specific command
ansible-pull
Usage: ansible-pull [options] [playbook.yml] ansible-pull: error: URL for repository not specified, use -h for help