EX294 Transform data with filters and plugins Practice Test 4 — 15 Questions

Question 1

A senior engineer needs to debug an Ansible playbook that uses lookups. Which TWO plugins can be used to retrieve data from a file on the control node? (Select exactly two.)

Accepted Answer

file. The `file` lookup plugin reads the content of a file from the control node's filesystem and returns it as a string. This is the standard way to retrieve file data directly from the Ansible control node without transferring the file to the managed host.

Answer

ini

Answer

password

Answer

csvfile

Question 2

Refer to the exhibit. After running the playbook, what is the value of 'clean_list'?

Accepted Answer

['apple', 'banana', 'cherry']. The `lower` filter converts all strings to lowercase, and the `map('trim')` filter removes leading and trailing whitespace from each element. The playbook applies these filters sequentially to the `fruits` list, resulting in `['apple', 'banana', 'cherry']`.

Answer

[' apple ', 'BANANA', '  cherry  ']

Answer

[' apple ', 'banana', '  cherry  ']

Answer

['APPLE', 'BANANA', 'CHERRY']

Question 3

Refer to the exhibit. Assuming the managed node is RHEL 7.9, what is the output of the debug task?

Accepted Answer

True. The debug task uses the `debug` module with `msg: "{{ ansible_distribution_version is version('7.9', '>=') }}"`. The `version` filter compares the string `'7.9'` (from `ansible_distribution_version`) against the string `'7.9'` using the `>=` operator. Since the managed node is RHEL 7.9, the comparison evaluates to `True`, so the debug module outputs `True`.

Answer

7.9

Answer

An error

Answer

False

Question 4

Refer to the exhibit. What is the output of the debug task?

Accepted Answer

192.168.1.10. The `debug` task in Ansible uses the `msg` parameter to display the value of a variable. In the exhibit, the variable `ansible_default_ipv4.address` is referenced, which returns the IPv4 address of the default network interface. Since the host's default interface is eth0 with IP 192.168.1.10, the debug output is that IP address. Option D correctly shows the output as '192.168.1.10'.

Answer

10.0.0.5

Answer

[ '192.168.1.10' ]

Answer

eth0

Question 5

An Ansible playbook retrieves a JSON response from an API and stores it in the variable `api_response`. The JSON structure is a list of objects, each with keys `name`, `status`, and `id`. The team needs to create a list of names for objects where status is 'active'. Which filter should be used?

Accepted Answer

{{ api_response | selectattr('status', 'equalto', 'active') | map(attribute='name') | list }}. It uses `selectattr` to filter the list of objects to only those where `status` equals 'active', then `map` to extract the `name` attribute from each filtered object, and finally `list` to convert the result into a list. This is the standard Ansible approach for filtering a list of dictionaries and extracting specific keys.

Answer

Answer

Answer

Question 6

An administrator needs to combine two dictionaries, `base_config` and `user_config`, where keys in `user_config` should override keys in `base_config`, and nested dictionaries should be merged recursively. Which filter syntax achieves this?

Accepted Answer

{{ base_config | combine(user_config, recursive=True) }}. The `combine` filter in Ansible with `recursive=True` merges two dictionaries, with `user_config` overriding `base_config`, and recursively merges nested dictionaries. This matches the requirement exactly, as `recursive=True` ensures that nested structures are combined rather than replaced outright.

Answer

Answer

Answer

Question 7

A developer wrote a custom filter plugin in a Python file `my_filters.py` and placed it in the directory `./filter_plugins/`. The playbook fails with 'ERROR! no filter named 'my_custom_filter''. The playbook is located in `/home/user/project/playbook.yml`. The `ansible.cfg` file in the same directory does not set `filter_plugins`. Which is the most likely cause?

Accepted Answer

The plugin file must be a Python module with a class named `FilterModule` and the filter function must be listed in the `filters` method. Ansible requires custom filter plugins to be Python modules that define a class named `FilterModule` with a `filters()` method returning a dictionary mapping filter names to their implementing functions. Without this structure, Ansible cannot discover or register the filter, causing the 'no filter named' error.

Answer

The filter file must be named `__init__.py`

Answer

The filter function must be imported in the playbook via `filter_plugins: my_filters`

Answer

The filter function name does not match the class name in the plugin

Question 8

An Ansible task uses the variable `{{ my_var | default(required=true) }}`. What happens if `my_var` is undefined?

Accepted Answer

The task fails with an error message. The `default(required=true)` filter in Ansible explicitly marks the variable as required. If `my_var` is undefined, the filter raises an error because it enforces that the variable must be provided, causing the task to fail with an error message. This is a deliberate mechanism to catch missing mandatory variables early in playbook execution.

Answer

The task skips the host

Answer

The task uses an empty string

Answer

The task uses the string 'required'

Question 9

Given a list of dictionaries `users` with keys `name` and `role`, a playbook needs to create a list of names where role is 'admin'. Which expression achieves this?

Accepted Answer

{{ users | selectattr('role', 'equalto', 'admin') | map(attribute='name') | list }}. It first uses `selectattr` to filter the list of dictionaries, keeping only those where `role` equals `'admin'`, then applies `map(attribute='name')` to extract the `name` values from the filtered dictionaries, and finally converts the result to a list with the `list` filter. This produces a list of names for admin users.

Answer

{{ users | map(attribute='name') | selectattr('role', 'equalto', 'admin') | list }}

Answer

{{ users | json_query("[?role=='admin'].{name: name}") }}

Answer

Question 10

A large-scale Ansible deployment processes a list of thousands of network devices. Using the `subelements` filter to iterate over interfaces is causing very slow playbook execution. Which approach can significantly improve performance?

Accepted Answer

Use a custom filter plugin in Python that uses list comprehensions. The `subelements` filter in Ansible processes nested data structures by iterating over each parent element and its child elements, which can be extremely slow for large datasets due to the overhead of Jinja2 template evaluation and repeated lookups. A custom filter plugin written in Python using list comprehensions avoids this overhead by executing native Python code directly, which is significantly faster because it operates at the interpreter level without the iterative Jinja2 expansion. This approach reduces the number of tasks and template evaluations, improving performance for thousands of network devices.

Answer

Use `with_nested` instead

Answer

Use `set_fact` with loops inside the task

Answer

Use `with_items` with `json_query` instead

Question 11

An Ansible playbook needs to extract the domain name from a list of email addresses stored in variable `emails`. The domain appears after the '@' symbol. Which filter should be used?

Accepted Answer

regex_replace. The `regex_replace` filter can extract the domain by matching the pattern `.*@(.*)` and replacing with `\1`, isolating the part after '@'. This is the correct approach because Ansible's Jinja2 filters include `regex_replace` for pattern-based string extraction, while `split` would require additional steps to isolate the domain.

Answer

split

Answer

urldecode

Answer

base64

Question 12

A playbook has a dictionary `config` that maps service names to ports. The team wants to iterate over both keys and values in a task. Which filter should be used to convert the dictionary into a list of key-value pairs?

Accepted Answer

dict2items. The `dict2items` filter is the correct choice because it converts a dictionary into a list of key-value pairs, each represented as a dictionary with `key` and `value` keys. This is the standard Ansible filter for iterating over both keys and values in a `loop` within a task, enabling access to `item.key` and `item.value`.

Answer

items2dict

Answer

flatten

Answer

json_query

Question 13

A custom filter plugin named `custom_filter` is stored in `./filter_plugins/` relative to the playbook. The playbook runs on a control node where the `ansible.cfg` sets `filter_plugins = /opt/ansible/filters`. Which location will Ansible search for the plugin first?

Accepted Answer

/opt/ansible/filters. Ansible's plugin loading order prioritizes the `filter_plugins` directory specified in `ansible.cfg` over the `./filter_plugins/` directory relative to the playbook. The `ansible.cfg` setting explicitly overrides the default search path, so `/opt/ansible/filters` is checked first.

Answer

Both A and B, with A first then B

Answer

./filter_plugins/

Answer

~/.ansible/plugins/filter

Question 14

Which TWO filters are commonly used to manipulate JSON data in Ansible? (Select exactly two.)

Accepted Answer

from_json. (from_json) is correct because it converts a JSON string into an Ansible data structure (dict or list), enabling further manipulation with filters like json_query. This is essential when parsing API responses or configuration files that return JSON-formatted strings.

Answer

flatten

Answer

regex_replace

Answer

to_json

Question 15

Which THREE are valid uses of lookup plugins in Ansible? (Select exactly three.)

Accepted Answer

Generate a random MAC address using `password` lookup with `mac` parameter. The `password` lookup plugin supports the `mac` parameter to generate a random MAC address. Option B is correct because the `password` lookup plugin is used to generate random passwords. Option D is correct because the `ini` lookup plugin retrieves values from INI files. Option C is incorrect: the `pipe` lookup plugin executes a command locally on the control node, not on the remote host. Option E is incorrect because the `file` lookup plugin reads the contents of a file from the control node, but it is not considered one of the three valid uses in this context.

Answer

Execute a command on the remote host using `pipe` lookup

Answer

Read the contents of a file using `file` lookup