Variables and Facts

Question 1

How do you define variables in playbook?

Answer 1

vars:
key_file: /usr/local/nginx.key
server_name: localohost

Question 2

How do you define variables in playbook using a file?

Answer 2

vars_files:

- nginx.yml

Question 3

How to log out the content of a variable?

Answer 3

• debug: var=variable name

Question 4

Put the result of executing a command in a variable

Answer 4

• name: capture current user into a varianle
  command: whoami
  register: login

Question 5

How do you prevent ansible from stoping execution of a task after encountering an error?

Answer 5

Add the flag ignore_errors: True to the task definition.

Question 6

What is the type of value received when using register clause?

Answer 6

dictionary. Though the list of fields depends on each module.

Question 7

How do you know what are the fields of the dictionary returned by the register clause?

Answer 7

Log the result and review the fields. Official documentation of modules often does not include the list of fields.

• name: log a registered variable
  command: whoami
  register: login
  debug: var=login

Question 8

Assume I use the register clause with the command module. The result populated by register is a dictionary. What field of this dictionary contains the true result of the command?

Answer 8

stdout

Question 9

If a variable “user” contains a dictionary, how do you access a key password of this dictionary?

Answer 9

{{ user.password }}

{{ user[‘password’] }}

Question 10

In what case can you use {{ user[‘name’] }} where you cannot use {{ user.name }}?

Answer 10

if the key of the dictionary contained in the variable ‘user’ has spaces. for instance {{ user[‘firstname and lastname’] }}

Question 11

What are facts?

Answer 11

Information Ansible gathers on the remote machine before running the playbook.

Question 12

Example of facts

Answer 12

CPU Architecture, Operating System, memory, disk info

Question 13

What is the ad-hoc command for retrieving facts?

Answer 13

ansible server -m setup

Question 14

What is the ad-hoc command for retrieving facts starting with ansible_eth?

Answer 14

ansible server -m setup -a “filter=ansible_eth*”

Question 15

Explain this: {{ ansible_local.example.book.title }}

Answer 15

This returns a fact named title defined under the group named book in a file named example.fact located at /etc/ansible/facts.d on one of the managed hosts.

Question 16

Explain local facts?

Answer 16

facts that are defined on a speicific machine by its owner or operator. This is different from standard facts such as memory and disk info that are collected by Ansible.

Question 17

How do you define local facts?

Answer 17

Define a file in ini format and store it under /etc/ansible/facts.d

Question 18

How do you display all tasks of a playbook?

Answer 18

ansible-playbook –list-tasks playbook.yml

Question 19

Can an ansible variable reference another variable?

Answer 19

Yes, definitely. Example:

venv_path: “{{ venv_home }}/{{ proj_name }}”

Question 20

What is the difference in the way the apt module and the pip modules handle list?

Answer 20

apt module will results in once single execution of apt with the list of packages passed as argument

pip will be called many times, once for each package in the list.

Question 21

We want to execute a task as root. what instruction do we use to facilitate this in the playbook?

Answer 21

• name: example of task that escalate priviledges
  apt : pkg=nginx update_cache=yes
  become: True