Introduction

Question 1

In what file do you specify information about servers that have to be managed by Ansible?

Answer 1

inventory file

Question 2

What is the command for running playbooks?

Answer 2

ansible-playbook

Question 3

What is ansible command for ad-hoc execution of commands?

Answer 3

ansible -i hosts -m ping

Question 4

In what order does ansible look for config file?

Answer 4

1) ANSIBLE_CONFIG env variable
2) ./ansible.cfg (current directory)
3) ~/.ansible.cfg (home folder)
4) /etc/ansible/ansible.cfg (Installation directory)

(ECHI)

Question 5

What is the prefered location for ansible config file?

Answer 5

current directory alongside playbooks

Question 6

Why put ansible config files alonside playbooks?

Answer 6

So they can be version controlled

Question 7

Example of variables that can be defined in ansible config file

Answer 7

1) Location of inventory file
2) User to SSH
3) SSH private keys

Question 8

What is the default location of ansible config?

Answer 8

/etc/ansible/ansible.cfg

Question 9

Command module for check uptime on testserver

Answer 9

ansible testserver -m command -a uptime

Question 10

Explain: ansible testserver -a uptime

Answer 10

Execute the command module to check uptime of remote server: testserver. -m command is ommitted because the command module is very often used.

Question 11

When running the command module what is the -b flag used for?

Answer 11

become root and run the command in priviledged mode

Question 12

What is a playbook?

Answer 12

An ansible configuration management script

Question 13

What is the very first line of a playbook?

Answer 13

three dash: —

Question 14

Strings in YAML?

Answer 14

1) “This is a string”

2) This is also a string

Question 15

Comments in YAML

Answer 15

This is a comment

Question 16

Booleans in YAML

Answer 16

true, True, TRUE, yes, Yes, YES, on, On, ON, y, Y

false, False, FALSE, no, No, NO, off, Off, OFF, n, N

Question 17

List in Ansible

Answer 17

• One
• Two
• Three

or

[One, Two, Three]

Question 18

Dictrionary or Mapping in Ansible

Answer 18

address: 742 Evergreen Terrace
city: Vancouver
state: North Dakota

Question 19

Define the structure of a playbook

Answer 19

A playbook is a list of plays, which themselves are dictionaries. So a playbook is a list of dictionaries.

Question 20

Define the structure of a play

Answer 20

A play is a dictionary that must include:

1) hosts to confiigure
2) A list of tasks, which themselves are dictionaries

The play connects hosts to tasks.

Question 21

Additional common settings of a play?

Answer 21

1) become
2) name
3) vars

Question 22

Sytructure of a task

Answer 22

1) Name

2) module : arguments (e.g. apt: name=nginx update_cache=yes)

Question 23

what are modules?

Answer 23

scripts that come with ansible and execute some sort of actions on the managed hosts

Question 24

Example of modules

Answer 24

apt, copy, file, template

Question 25

How do you get documentation on a module such as “copy”?

Answer 25

ansible-doc copy

Question 26

Sum up the structure of a playbook?

Answer 26

1) A playbook is a list of plays
2) A plays ties an unordered set of hosts to an ordered list of tasks
3) Each task is associated with exactly one module

Question 27

How do you reference a variable “var” in a playbook?

Answer 27

{{ braces }}

Question 28

When do you have to quote variable reference?

Answer 28

When it starts the argument part of a module declaration. 
For instance: 
command: {{  braces }} - a foo

Should be replaced with:
command: “{{ braces }} - a foo”

Question 29

What problems do you encounter if your command argument contain colon?

Answer 29

The colon makes ansible believe that your argument is a dictionary. This is solve by quoting the argument again.

However, in the case of debug module double quote is needed.

• name: show a debug message
  debug: “msg=’This is a message: eh?’”

Question 30

What is a handler?

Answer 30

A handler is a conditional structure similar to a task. It is triggered only if it has been notified by a task.

Question 31

How does a task notify a handler?

Answer 31

It includes the notify instruction along with the name of the handler as argument.

• name: Copy TLS certs
  copy: source dest
  notify: restart nginx

Question 32

How many times can a handler run in the execution of a playbook and when?

Answer 32

A handler runs only once after all the tasks are run at the end of the play. Even if the handler is notified multiple times, it runs only once.

Question 33

Many handlers are defined in a play. In which order will they be executed?

Answer 33

In the order in which they are defined in the play NOT in the order in which they are notified.

Question 34

What are typical use cases for handlers?

Answer 34

1) restarting services (more frequent)

2) reboot

Question 35

Give two orchestration scenarios that are good for Ansible?

Answer 35

1) Upgrading web application behind a load balancer one after the other
2) Making sure DB is started and configured before web app starts

Question 36

Write a task to install nginx on an Ubuntu node

Answer 36

• name: Install nginx

apt: name=nginx

Question 37

Why is Ansible push model interesting?

Answer 37

You have full control on when the changes are applied and you do not need to wait for timers to expire.

Question 38

What is the advantage of idempotency?

Answer 38

It’s safe to run an Ansible playbook multiple times against a server

Question 39

Write a task to create a user

Answer 39

• name: Create user deploy

user: name=deploy group=web

Question 40

Example of activity that goes into a pre-handler

Answer 40

Update the apt cache on Ubuntu

Question 41

What happens when a host is defined in many groups with different set of variables?

Answer 41

The variable set are merged and the precedence rule applies

Question 42

How do you validate connectivity to a host?

Answer 42

ansible host -m ping

Question 43

Give example of two modules that are not idempotent

Answer 43

command and shell

Question 44

Is command module idempotent?

Answer 44

No, command and shell modules are not idempotemt

Question 45

Is shell module idempotemt?

Answer 45

No, command and shell modules are not idempotemt

Question 46

What is a module?

Answer 46

encapsulated procedure that is responsible for managing a specific component on a specific platform.

Question 47

What is battery-included approach?

Answer 47

The fact that Ansible includes tones of modules built-in.