JNCIA-DevOps Data Serialization — All Questions With Answers

An automation script reads a multi-document YAML file containing configuration templates for various Junos router models. To process each document individually in Python using PyYAML, which function should the engineer invoke?

Question 2easymultiple choice

An automation engineer is writing a Python script to parse a Juniper Junos NETCONF reply received in XML format and needs to convert it into a native Python dictionary for internal processing. Which built-in library should the engineer use to convert the structured XML tree?

Question 3hardmultiple choice

A Python script receives a JSON payload from a Junos device containing 64-bit interface counter integers. When loaded using the standard 'json' module, the script experiences precision loss on counter values exceeding standard integer limits. Which alternative JSON parser package for Python should be used to handle high-precision integers without data degradation?

Question 4easymultiple choice

What is the primary delimiter used to separate key-value pairs in a JSON object?

Question 5easymultiple choice

Which symbol represents the beginning of a single YAML document stream?

Question 6hardmultiple choice

When parsing a Junos configuration snippet in YAML, an engineer notices a string value starting with a zero (e.g., '01234') that is unquoted. How do YAML parsers typically interpret this value?

Question 7mediummultiple choice

An automation engineer is writing a Python script to push configurations to a Junos device. The script loads a YAML data file containing interface descriptions. One description contains a colon without a following space (e.g., 'Interface:Primary'). What error will PyYAML raise when attempting to parse this file?

Question 8hardmulti select

When working with PyYAML in Python for Junos automation scripts, which THREE of the following practices enhance script security and robustness? (Choose three)

Question 9mediummulti select

Which TWO Python exceptions might be raised when attempting to parse a malformed JSON string using the standard 'json' module? (Choose two)

Question 10hardmultiple choice

An automation script needs to convert a JSON string containing Juniper interface statistics into a YAML format to maintain consistency with existing Ansible variable files. When performing this conversion, which structural capability does YAML support that standard JSON does not?

Question 11hardmulti select

You are writing a Python script to convert a complex Juniper device inventory from YAML format into JSON format using PyYAML and the built-in json module. Which THREE considerations must you keep in mind regarding differences between YAML and JSON during this conversion? (Choose three)

Question 12easymultiple choice

An automation engineer is converting a Junos device's REST API response into a YAML configuration file. The JSON response includes a field "interface_name": null, which indicates that no physical interface is currently assigned. The engineer wants to preserve this information in the YAML file so that the automation script can distinguish between a missing key and an explicitly empty value. Which YAML representation should the engineer use for this field?

Question 13mediummultiple choice

A network automation engineer is writing a Python script that uses the json module to parse a Junos REST API response. The response contains a JSON object with a key "interface-speed" set to the string "10G". The engineer needs to access this value and convert it to an integer representing megabits per second (10000). Which Python code snippet correctly retrieves and converts the value?

Question 14mediummultiple choice

A developer is writing a Python script that reads a Junos device inventory file. The team wants to use a data format that is a strict subset of JavaScript object notation, supports comments, and allows trailing commas. Which data format best fits these requirements?

Question 15easymultiple choice

An automation engineer runs a Python script that calls the Junos REST API on an SRX Series device and receives an interface description as the JSON value "100". The script then passes that value to a Junos CLI command built with PyEZ. Which JSON data type is "100" when the response is decoded by the script?

Question 16mediummultiple choice

An automation engineer stores Junos device facts in a YAML file used by a PyEZ script. The file currently contains:

interfaces:

- ge-0/0/0 - ge-0/0/1

management_ip: 192.0.2.10

The script needs to add a second management address, 192.0.2.11, as a list while keeping the file valid YAML. Which YAML snippet correctly represents management_ip as a two-element sequence?

Question 17easymultiple choice

A network automation engineer exports the running configuration of a Junos device to a file named `backup.conf` and wants to parse it with a Python script using a data serialization library so that interface names, descriptions, and IP addresses can be accessed programmatically. Which data serialization format is the most appropriate for this task?

Question 18hardmulti select

An automation engineer is comparing JSON and YAML for serializing Junos device inventory data that will be consumed by multiple tools. Which TWO statements correctly describe intrinsic characteristics of these formats? (Choose two.)

Question 19easymultiple choice

An engineer needs to represent an ordered list of IP addresses in a YAML configuration file for a Junos automation playbook. Which valid YAML syntax correctly defines a sequence of items?

Question 20mediummultiple choice

A Python script retrieves interface statistics from a Junos device in JSON format, modifies a threshold value, and needs to output it back into a formatted JSON string with an indentation level of 4 spaces for readability. Which Python snippet achieves this?

Question 21mediummultiple choice

An automation engineer is writing a Python script that takes a complex nested Python dictionary containing Junos telemetry parameters and converts it into a YAML string. Which PyYAML function should be used?

Question 22mediummultiple choice

A network automation script is reading a YAML configuration file containing Junos device credentials. The script encounters an unhandled exception when attempting to load the file using PyYAML. Upon inspection, the error is caused by a tab character used for indentation instead of spaces. Which YAML specification rule does this violate?

Question 23hardmultiple choice

You are writing a Python automation script that processes JSON output from a Junos device's 'show interfaces' operational command via PyEZ. One of the interface descriptions contains raw control characters. When the script attempts to dump this data to a JSON string using json.dumps(), it raises a ValueError. Which parameter should you pass to json.dumps() to handle non-printable or out-of-range character encoding gracefully?

Question 24easymultiple choice

Which of the following data types is natively supported in JSON without requiring custom serialization handlers?

Question 25easymultiple choice

Which character is used to indicate a mapping key-value pair in YAML syntax?

Question 26easymultiple choice

Which file extension is conventionally used for YAML data serialization files?

Question 27easymultiple choice

Which of the following characters is used to start a comment line in a YAML document?

Question 28mediummultiple choice

An automation engineer needs to convert a JSON payload representing Junos interface configurations into equivalent YAML format to reuse in an Ansible playbook. Which fundamental structural relationship between JSON and YAML makes this conversion straightforward?

Question 29mediummultiple choice

An automation scripter needs to load a YAML configuration file in Python. To prevent arbitrary code execution vulnerabilities associated with untrusted files, which function should always be called?

Question 30hardmultiple choice

When converting a deeply nested JSON data structure representing Junos device health metrics into YAML using PyYAML, the output uses complex block styles that are difficult for team members to read. Which parameter in yaml.safe_dump() can force scalar values or containers to prefer flow style (JSON-like curly braces and brackets) instead?

Question 31hardmultiple choice

A Python script reads a Junos configuration snippet stored in YAML. The configuration uses YAML anchors and aliases to duplicate common routing policy definitions across multiple VRFs. When the script parses the file using yaml.safe_load(), what happens to the anchors and aliases?

Question 32mediummultiple choice

An automation engineer wants to log structured data from a Junos device automation run. The Python script formats a dictionary into a JSON string and prints it. However, the engineer wants all keys sorted alphabetically to ensure consistent log diffing. Which parameter accomplishes this in json.dumps()?

Question 33easymultiple choice

Open the full BGP breakdown →

What type of brackets enclose an array in a JSON document?

Question 34hardmultiple choice

A Python script processes a YAML configuration template for Junos BGP neighbors. The configuration contains a multi-line banner string description. Which YAML block scalar indicator preserves newlines exactly as written in the text block?

Question 35mediummultiple choice

An automation engineer writes a Python script that reads a Junos configuration file serialized in JSON. The file opens successfully, but parsing fails with a JSONDecodeError due to trailing commas at the end of object lists. How does standard JSON handle trailing commas compared to YAML?

Question 36hardmultiple choice

When writing a Python script to interact with a Junos device via PyEZ, you receive an object representing RPC output. You want to serialize a custom Python class instance containing device metadata into JSON, but calling json.dumps() raises a TypeError. What is the standard approach to resolve this?

Question 37mediummultiple choice

An automation script reads a configuration template where boolean values are represented as 'yes' and 'no' in YAML. When parsed using PyYAML in Python, how are these values interpreted?

Question 38hardmultiple choice

You are writing a Python automation script that reads a Junos configuration file in JSON format. The JSON file contains duplicate keys within the same object scope. According to the JSON specification RFC 8259, how should a conforming JSON parser handle duplicate keys?

Question 39easymultiple choice

Which Python module is part of the standard library and provides functions to serialize and deserialize JSON data?

Question 40mediummultiple choice

An automation engineer is writing a script that saves operational telemetry data gathered from a Junos router. The data needs to be written directly to an open file stream in JSON format. Which method from the Python 'json' module should be used?

Question 41mediummultiple choice

An engineer needs to convert an existing YAML-formatted inventory file into JSON format using a Python script. Which workflow accomplishes this transformation?

Question 42hardmultiple choice

You are writing a Python automation tool that reads telemetry data from a Junos device. The data is received as a JSON string containing forward slashes escaped as '\/'. When you load this string using json.loads(), how does Python handle the escaped slashes?

Question 43easymultiple choice

Which Python function deserializes a JSON-formatted string into a native Python dictionary?

Question 44easymultiple choice

Which of the following describes the fundamental structural difference between JSON and YAML regarding syntax design?

Question 45hardmultiple choice

A Python automation script parses a Junos telemetry stream in JSON. The JSON payload uses integer keys in a dictionary (e.g., {443: 'HTTPS'}). When loaded into Python using json.loads(), what data type do the dictionary keys become?

Question 46mediummultiple choice

An automation engineer needs to include comments explaining complex network parameters inside a Junos automation data file. Which serialization format should the engineer select?

Question 47hardmultiple choice

You are writing a Python script that parses a multi-document YAML stream containing Junos device site configurations. One of the documents contains a custom YAML tag. When parsing with yaml.safe_load_all(), how does the safe loader handle custom tags?

Question 48easymultiple choice

Read the full REST/YANG explanation →

Which of the following valid JSON values represents a boolean true state?

Question 49easymultiple choice

What is the native data format returned by Junos devices when queried via REST API or NETCONF operations configured with JSON output formatting?

Question 50mediummultiple choice

An automation engineer wants to verify the syntax of a large YAML playbook before executing it against a production Junos device. Which python one-liner command can be run in the terminal to quickly check if the file is syntactically valid YAML?

Question 51hardmultiple choice

Open the full VLAN trunking answer →

A Python automation script extracts routing table entries from a Junos device. The data structure contains deeply nested dictionaries and lists. The engineer needs to perform a deep copy of this deserialized JSON structure before modifying it. Which Python module provides the deepcopy function needed to duplicate nested containers safely?

Question 52mediummultiple choice

An automation script reads interface names and VLAN IDs from a CSV file and converts each row into a JSON object before sending it to a Junos device REST API. Which Python module is specifically designed to parse CSV (Comma-Separated Values) files?

Question 53hardmultiple choice

You are writing a Python script that converts a Junos operational state output from XML (via NETCONF) into JSON. The XML structure contains sibling elements with the same tag name. When converted naively, how do standard XML-to-JSON conversion libraries (like xmltodict) typically represent these repeated sibling elements in the resulting JSON dictionary?

Question 54easymultiple choice

Which of the following primitive data types is NOT supported natively in JSON?

Question 55easymulti select

Which TWO of the following are valid primitive data types in JSON? (Choose two)

Question 56mediummultiple choice

An automation engineer needs to pretty-print a JSON payload in the Linux terminal for debugging Junos telemetry. Which built-in Python command-line utility can be invoked to validate and pretty-print a JSON file?

Question 57hardmultiple choice

You are writing a Python automation script that processes configuration data. The script reads a YAML file containing Junos firewall filters, modifies them, and writes them back out. However, you notice that all the original comments in the file are stripped out in the output. What is the fundamental reason for this behavior in standard PyYAML dump operations?

Question 58easymulti select

Which TWO of the following are valid extensions commonly used for YAML files? (Choose two)

Question 59mediummulti select

Which TWO methods are provided by the Python standard library 'json' module for deserializing JSON data? (Choose two)

Question 60mediummulti select

Which TWO features are supported by YAML but are notably absent in standard JSON? (Choose two)

Question 61hardmulti select

When serializing Python data structures to JSON for Junos automation payloads, which THREE parameters can be passed to json.dumps() to control formatting and readability? (Choose three)

Question 62easymulti select

Which TWO of the following are valid scalar values in a YAML document? (Choose two)

Question 63mediummulti select

Which TWO Python standard library modules are commonly combined when a script needs to fetch web content (such as Junos REST API data) and parse the resulting payload? (Choose two)

Question 64easymulti select

Which TWO characters or sequences are valid in YAML for representing lists or sequences? (Choose two)

Question 65hardmulti select

When serializing complex nested Python dictionaries to JSON, which THREE data types will cause a TypeError unless handled by a custom default encoder function? (Choose three)

Question 66hardmulti select

When writing an automation script that converts data formats between YAML and JSON for Junos configuration pipelines, which THREE potential pitfalls should an engineer account for? (Choose three)

Question 67easymultiple choice

An automation engineer is writing a Python script to parse a Juniper Junos NETCONF reply received in XML format and needs to convert it into a JSON structure for easier manipulation in a web application. Which built-in Python module is primarily used to handle JSON data serialization and deserialization?

Question 68mediummultiple choice

An engineer receives a YAML configuration snippet for a PyEZ automation script, but the script fails with a parser error. Upon inspection, the error is caused by improper indentation levels. Which rule must be strictly followed regarding indentation in YAML syntax?

Question 69hardmultiple choice

You are writing a Python script using the PyEZ library to retrieve interface facts from a Juniper EX Series switch. The resulting data structure is stored in a Python dictionary. You need to dump this dictionary into a YAML file so it can be read by an Ansible playbook later. Which PyYAML function should you use to convert the Python dictionary into a YAML-formatted string or file stream?

Question 70easymultiple choice

An automation developer is examining a JSON response payload returned by a Juniper device via a REST API call. Which valid JSON data type is used to represent an ordered list of values enclosed within square brackets?

Question 71mediummultiple choice

During script development, an engineer encounters a YAML file containing comments and multiple configuration documents separated by document markers. Which characters are used to denote the start of a new document within a single YAML file stream?

Question 72mediummulti select

An automation engineer is reviewing data serialization formats used within Junos automation workflows. Which TWO statements are correct regarding JSON syntax and data types? (Choose two)

Question 73mediummultiple choice

An engineer writes a Python script that loads a JSON configuration file using the json.load() method. The file contains configuration parameters for a Junos device. If the JSON file contains a trailing comma at the end of the last element in an array, what will happen when the script executes?

Question 74easymulti select

An automation developer is designing a script that reads routing policy parameters from a configuration file. Which TWO data formats are natively supported and commonly used across Junos automation toolchains like PyEZ, Ansible, and REST APIs for data serialization? (Choose two)

Question 75mediummultiple choice

A network automation engineer is using a Python script with the PyYAML library to load a YAML file that defines a Junos device's configuration. The script needs to ensure that the loaded data is a Python dictionary and that no arbitrary Python objects are instantiated during parsing. Which function should the engineer use to safely load the YAML content?

Question 76hardmulti select

An automation engineer is designing a Python script that converts Junos device configuration data between JSON and YAML formats. The script must correctly handle data types to avoid misconfiguration. Which TWO statements about JSON and YAML data type handling are correct? (Choose two.)

Question 77easymultiple choice

An automation engineer stores Junos interface descriptions in a YAML file. One description includes the text 'Link: 10G uplink to core-sw-01'. After loading the file with a standard YAML parser, the engineer finds the value is not parsed as expected. Which YAML syntax should the engineer use to store this value correctly?

Question 78mediummultiple choice

A network automation team stores Junos device inventory in JSON. A developer notices that the JSON file contains a field "last_updated": "2024-05-01T12:00:00Z" and wants to compare it against the current time in a Python script. Which statement correctly describes how a standard JSON parser handles this value?

Question 79hardmultiple choice

An automation engineer is building a Python script that generates Junos configuration snippets from a JSON payload. The payload contains nested objects representing interfaces, units, and addresses. The engineer uses json.loads and then accesses data['interfaces']['ge-0/0/0']['unit'][0]['family']['inet']['address'][0]['name']. Which JSON structural feature makes this nested access pattern possible?

Question 80hardmulti select

An automation engineer is comparing YAML and JSON for storing Junos device configuration data. Which TWO statements accurately describe differences between the two formats? (Choose two.)

Question 81mediummultiple choice

An automation engineer uses a Python script to pull interface statistics from a Junos device through the Junos PyEZ Table and View framework. The View definition must map the XML element <name> to the Python attribute interface_name. Which PyEZ View syntax correctly performs this mapping?

Question 82mediummultiple choice

An automation engineer uses a Python script with the PyEZ library to retrieve interface statistics from a Junos device and wants to store the results in a file that preserves data types such as integers, booleans, and null values for later processing by another tool. The engineer needs a serialization format that is compact, widely supported by APIs, and preserves these primitive types. Which format should the engineer choose?

Question 83hardmulti select

An automation engineer is designing a data model for Junos device inventory that will be serialized to JSON and consumed by multiple tools. The engineer wants to include a null value, a boolean, and a string that contains a colon and a space. Which TWO statements correctly describe JSON serialization rules that apply to this model? (Choose two.)

Question 84hardmultiple choice

An automation engineer writes a Python script that loads a YAML file containing Junos device connection parameters. The file includes a line `timeout: 30` and another line `description: 30 seconds`. The script then uses the values in a template. Which statement correctly describes how a standard YAML parser will interpret these two scalar values?

Question 85hardmultiple choice

An automation engineer writes a Python script that reads a Junos configuration exported as JSON and uses json.loads to parse it. The script then searches for a key named "interfaces". The JSON document contains two objects at the same nesting level, each with an "interfaces" key, because the configuration was merged from two sources. What will json.loads produce, and how should the script handle it?

Question 86mediummultiple choice

An automation engineer needs to parse a JSON payload returned by the Junos REST API that contains a list of interfaces, each with a name and a list of addresses. The engineer wants to iterate over the interfaces and then over each interface's addresses in Python. Which Python data structure mapping does the `json` module produce for this payload?

Question 1hardmultiple choice

An automation script reads a multi-document YAML file containing configuration templates for various Junos router models. To process each document individually in Python using PyYAML, which function should the engineer invoke?

Question 2easymultiple choice

An automation engineer is writing a Python script to parse a Juniper Junos NETCONF reply received in XML format and needs to convert it into a native Python dictionary for internal processing. Which built-in library should the engineer use to convert the structured XML tree?

Question 3hardmultiple choice

A Python script receives a JSON payload from a Junos device containing 64-bit interface counter integers. When loaded using the standard 'json' module, the script experiences precision loss on counter values exceeding standard integer limits. Which alternative JSON parser package for Python should be used to handle high-precision integers without data degradation?

Question 4easymultiple choice

What is the primary delimiter used to separate key-value pairs in a JSON object?

Question 5easymultiple choice

Which symbol represents the beginning of a single YAML document stream?

Question 6hardmultiple choice

When parsing a Junos configuration snippet in YAML, an engineer notices a string value starting with a zero (e.g., '01234') that is unquoted. How do YAML parsers typically interpret this value?

Question 7mediummultiple choice

An automation engineer is writing a Python script to push configurations to a Junos device. The script loads a YAML data file containing interface descriptions. One description contains a colon without a following space (e.g., 'Interface:Primary'). What error will PyYAML raise when attempting to parse this file?

Question 8hardmulti select

When working with PyYAML in Python for Junos automation scripts, which THREE of the following practices enhance script security and robustness? (Choose three)

Question 9mediummulti select

Which TWO Python exceptions might be raised when attempting to parse a malformed JSON string using the standard 'json' module? (Choose two)

Question 10hardmultiple choice

An automation script needs to convert a JSON string containing Juniper interface statistics into a YAML format to maintain consistency with existing Ansible variable files. When performing this conversion, which structural capability does YAML support that standard JSON does not?

Question 11hardmulti select

You are writing a Python script to convert a complex Juniper device inventory from YAML format into JSON format using PyYAML and the built-in json module. Which THREE considerations must you keep in mind regarding differences between YAML and JSON during this conversion? (Choose three)

Question 12easymultiple choice

An automation engineer is converting a Junos device's REST API response into a YAML configuration file. The JSON response includes a field "interface_name": null, which indicates that no physical interface is currently assigned. The engineer wants to preserve this information in the YAML file so that the automation script can distinguish between a missing key and an explicitly empty value. Which YAML representation should the engineer use for this field?

Question 13mediummultiple choice

A network automation engineer is writing a Python script that uses the json module to parse a Junos REST API response. The response contains a JSON object with a key "interface-speed" set to the string "10G". The engineer needs to access this value and convert it to an integer representing megabits per second (10000). Which Python code snippet correctly retrieves and converts the value?

Question 14mediummultiple choice

A developer is writing a Python script that reads a Junos device inventory file. The team wants to use a data format that is a strict subset of JavaScript object notation, supports comments, and allows trailing commas. Which data format best fits these requirements?

Question 15easymultiple choice

An automation engineer runs a Python script that calls the Junos REST API on an SRX Series device and receives an interface description as the JSON value "100". The script then passes that value to a Junos CLI command built with PyEZ. Which JSON data type is "100" when the response is decoded by the script?

Question 16mediummultiple choice

An automation engineer stores Junos device facts in a YAML file used by a PyEZ script. The file currently contains:

interfaces:

- ge-0/0/0 - ge-0/0/1

management_ip: 192.0.2.10

The script needs to add a second management address, 192.0.2.11, as a list while keeping the file valid YAML. Which YAML snippet correctly represents management_ip as a two-element sequence?

Question 17easymultiple choice

A network automation engineer exports the running configuration of a Junos device to a file named `backup.conf` and wants to parse it with a Python script using a data serialization library so that interface names, descriptions, and IP addresses can be accessed programmatically. Which data serialization format is the most appropriate for this task?

Question 18hardmulti select

An automation engineer is comparing JSON and YAML for serializing Junos device inventory data that will be consumed by multiple tools. Which TWO statements correctly describe intrinsic characteristics of these formats? (Choose two.)

Question 19easymultiple choice

An engineer needs to represent an ordered list of IP addresses in a YAML configuration file for a Junos automation playbook. Which valid YAML syntax correctly defines a sequence of items?

Question 20mediummultiple choice

A Python script retrieves interface statistics from a Junos device in JSON format, modifies a threshold value, and needs to output it back into a formatted JSON string with an indentation level of 4 spaces for readability. Which Python snippet achieves this?

Question 21mediummultiple choice

An automation engineer is writing a Python script that takes a complex nested Python dictionary containing Junos telemetry parameters and converts it into a YAML string. Which PyYAML function should be used?

Question 22mediummultiple choice

A network automation script is reading a YAML configuration file containing Junos device credentials. The script encounters an unhandled exception when attempting to load the file using PyYAML. Upon inspection, the error is caused by a tab character used for indentation instead of spaces. Which YAML specification rule does this violate?

Question 23hardmultiple choice

You are writing a Python automation script that processes JSON output from a Junos device's 'show interfaces' operational command via PyEZ. One of the interface descriptions contains raw control characters. When the script attempts to dump this data to a JSON string using json.dumps(), it raises a ValueError. Which parameter should you pass to json.dumps() to handle non-printable or out-of-range character encoding gracefully?

Question 24easymultiple choice

Which of the following data types is natively supported in JSON without requiring custom serialization handlers?

Question 25easymultiple choice

Which character is used to indicate a mapping key-value pair in YAML syntax?

Question 26easymultiple choice

Which file extension is conventionally used for YAML data serialization files?

Question 27easymultiple choice

Which of the following characters is used to start a comment line in a YAML document?

Question 28mediummultiple choice

An automation engineer needs to convert a JSON payload representing Junos interface configurations into equivalent YAML format to reuse in an Ansible playbook. Which fundamental structural relationship between JSON and YAML makes this conversion straightforward?

Question 29mediummultiple choice

An automation scripter needs to load a YAML configuration file in Python. To prevent arbitrary code execution vulnerabilities associated with untrusted files, which function should always be called?

Question 30hardmultiple choice

When converting a deeply nested JSON data structure representing Junos device health metrics into YAML using PyYAML, the output uses complex block styles that are difficult for team members to read. Which parameter in yaml.safe_dump() can force scalar values or containers to prefer flow style (JSON-like curly braces and brackets) instead?

Question 31hardmultiple choice

A Python script reads a Junos configuration snippet stored in YAML. The configuration uses YAML anchors and aliases to duplicate common routing policy definitions across multiple VRFs. When the script parses the file using yaml.safe_load(), what happens to the anchors and aliases?

Question 32mediummultiple choice

An automation engineer wants to log structured data from a Junos device automation run. The Python script formats a dictionary into a JSON string and prints it. However, the engineer wants all keys sorted alphabetically to ensure consistent log diffing. Which parameter accomplishes this in json.dumps()?

Question 33easymultiple choice

Open the full BGP breakdown →

What type of brackets enclose an array in a JSON document?

Question 34hardmultiple choice

A Python script processes a YAML configuration template for Junos BGP neighbors. The configuration contains a multi-line banner string description. Which YAML block scalar indicator preserves newlines exactly as written in the text block?

Question 35mediummultiple choice

An automation engineer writes a Python script that reads a Junos configuration file serialized in JSON. The file opens successfully, but parsing fails with a JSONDecodeError due to trailing commas at the end of object lists. How does standard JSON handle trailing commas compared to YAML?

Question 36hardmultiple choice

When writing a Python script to interact with a Junos device via PyEZ, you receive an object representing RPC output. You want to serialize a custom Python class instance containing device metadata into JSON, but calling json.dumps() raises a TypeError. What is the standard approach to resolve this?

Question 37mediummultiple choice

An automation script reads a configuration template where boolean values are represented as 'yes' and 'no' in YAML. When parsed using PyYAML in Python, how are these values interpreted?

Question 38hardmultiple choice

You are writing a Python automation script that reads a Junos configuration file in JSON format. The JSON file contains duplicate keys within the same object scope. According to the JSON specification RFC 8259, how should a conforming JSON parser handle duplicate keys?

Question 39easymultiple choice

Which Python module is part of the standard library and provides functions to serialize and deserialize JSON data?

Question 40mediummultiple choice

An automation engineer is writing a script that saves operational telemetry data gathered from a Junos router. The data needs to be written directly to an open file stream in JSON format. Which method from the Python 'json' module should be used?

Question 41mediummultiple choice

An engineer needs to convert an existing YAML-formatted inventory file into JSON format using a Python script. Which workflow accomplishes this transformation?

Question 42hardmultiple choice

You are writing a Python automation tool that reads telemetry data from a Junos device. The data is received as a JSON string containing forward slashes escaped as '\/'. When you load this string using json.loads(), how does Python handle the escaped slashes?

Question 43easymultiple choice

Which Python function deserializes a JSON-formatted string into a native Python dictionary?

Question 44easymultiple choice

Which of the following describes the fundamental structural difference between JSON and YAML regarding syntax design?

Question 45hardmultiple choice

A Python automation script parses a Junos telemetry stream in JSON. The JSON payload uses integer keys in a dictionary (e.g., {443: 'HTTPS'}). When loaded into Python using json.loads(), what data type do the dictionary keys become?

Question 46mediummultiple choice

An automation engineer needs to include comments explaining complex network parameters inside a Junos automation data file. Which serialization format should the engineer select?

Question 47hardmultiple choice

You are writing a Python script that parses a multi-document YAML stream containing Junos device site configurations. One of the documents contains a custom YAML tag. When parsing with yaml.safe_load_all(), how does the safe loader handle custom tags?

Question 48easymultiple choice

Read the full REST/YANG explanation →

Which of the following valid JSON values represents a boolean true state?

Question 49easymultiple choice

What is the native data format returned by Junos devices when queried via REST API or NETCONF operations configured with JSON output formatting?

Question 50mediummultiple choice

An automation engineer wants to verify the syntax of a large YAML playbook before executing it against a production Junos device. Which python one-liner command can be run in the terminal to quickly check if the file is syntactically valid YAML?

Question 51hardmultiple choice

Open the full VLAN trunking answer →

A Python automation script extracts routing table entries from a Junos device. The data structure contains deeply nested dictionaries and lists. The engineer needs to perform a deep copy of this deserialized JSON structure before modifying it. Which Python module provides the deepcopy function needed to duplicate nested containers safely?

Question 52mediummultiple choice

An automation script reads interface names and VLAN IDs from a CSV file and converts each row into a JSON object before sending it to a Junos device REST API. Which Python module is specifically designed to parse CSV (Comma-Separated Values) files?

Question 53hardmultiple choice

You are writing a Python script that converts a Junos operational state output from XML (via NETCONF) into JSON. The XML structure contains sibling elements with the same tag name. When converted naively, how do standard XML-to-JSON conversion libraries (like xmltodict) typically represent these repeated sibling elements in the resulting JSON dictionary?

Question 54easymultiple choice

Which of the following primitive data types is NOT supported natively in JSON?

Question 55easymulti select

Which TWO of the following are valid primitive data types in JSON? (Choose two)

Question 56mediummultiple choice

An automation engineer needs to pretty-print a JSON payload in the Linux terminal for debugging Junos telemetry. Which built-in Python command-line utility can be invoked to validate and pretty-print a JSON file?

Question 57hardmultiple choice

You are writing a Python automation script that processes configuration data. The script reads a YAML file containing Junos firewall filters, modifies them, and writes them back out. However, you notice that all the original comments in the file are stripped out in the output. What is the fundamental reason for this behavior in standard PyYAML dump operations?

Question 58easymulti select

Which TWO of the following are valid extensions commonly used for YAML files? (Choose two)

Question 59mediummulti select

Which TWO methods are provided by the Python standard library 'json' module for deserializing JSON data? (Choose two)

Question 60mediummulti select

Which TWO features are supported by YAML but are notably absent in standard JSON? (Choose two)

Question 61hardmulti select

When serializing Python data structures to JSON for Junos automation payloads, which THREE parameters can be passed to json.dumps() to control formatting and readability? (Choose three)

Question 62easymulti select

Which TWO of the following are valid scalar values in a YAML document? (Choose two)

Question 63mediummulti select

Which TWO Python standard library modules are commonly combined when a script needs to fetch web content (such as Junos REST API data) and parse the resulting payload? (Choose two)

Question 64easymulti select

Which TWO characters or sequences are valid in YAML for representing lists or sequences? (Choose two)

Question 65hardmulti select

When serializing complex nested Python dictionaries to JSON, which THREE data types will cause a TypeError unless handled by a custom default encoder function? (Choose three)

Question 66hardmulti select

When writing an automation script that converts data formats between YAML and JSON for Junos configuration pipelines, which THREE potential pitfalls should an engineer account for? (Choose three)

Question 67easymultiple choice

An automation engineer is writing a Python script to parse a Juniper Junos NETCONF reply received in XML format and needs to convert it into a JSON structure for easier manipulation in a web application. Which built-in Python module is primarily used to handle JSON data serialization and deserialization?

Question 68mediummultiple choice

An engineer receives a YAML configuration snippet for a PyEZ automation script, but the script fails with a parser error. Upon inspection, the error is caused by improper indentation levels. Which rule must be strictly followed regarding indentation in YAML syntax?

Question 69hardmultiple choice

You are writing a Python script using the PyEZ library to retrieve interface facts from a Juniper EX Series switch. The resulting data structure is stored in a Python dictionary. You need to dump this dictionary into a YAML file so it can be read by an Ansible playbook later. Which PyYAML function should you use to convert the Python dictionary into a YAML-formatted string or file stream?

Question 70easymultiple choice

An automation developer is examining a JSON response payload returned by a Juniper device via a REST API call. Which valid JSON data type is used to represent an ordered list of values enclosed within square brackets?

Question 71mediummultiple choice

During script development, an engineer encounters a YAML file containing comments and multiple configuration documents separated by document markers. Which characters are used to denote the start of a new document within a single YAML file stream?

Question 72mediummulti select

An automation engineer is reviewing data serialization formats used within Junos automation workflows. Which TWO statements are correct regarding JSON syntax and data types? (Choose two)

Question 73mediummultiple choice

An engineer writes a Python script that loads a JSON configuration file using the json.load() method. The file contains configuration parameters for a Junos device. If the JSON file contains a trailing comma at the end of the last element in an array, what will happen when the script executes?

Question 74easymulti select

An automation developer is designing a script that reads routing policy parameters from a configuration file. Which TWO data formats are natively supported and commonly used across Junos automation toolchains like PyEZ, Ansible, and REST APIs for data serialization? (Choose two)

Question 75mediummultiple choice

A network automation engineer is using a Python script with the PyYAML library to load a YAML file that defines a Junos device's configuration. The script needs to ensure that the loaded data is a Python dictionary and that no arbitrary Python objects are instantiated during parsing. Which function should the engineer use to safely load the YAML content?

Question 76hardmulti select

An automation engineer is designing a Python script that converts Junos device configuration data between JSON and YAML formats. The script must correctly handle data types to avoid misconfiguration. Which TWO statements about JSON and YAML data type handling are correct? (Choose two.)

Question 77easymultiple choice

An automation engineer stores Junos interface descriptions in a YAML file. One description includes the text 'Link: 10G uplink to core-sw-01'. After loading the file with a standard YAML parser, the engineer finds the value is not parsed as expected. Which YAML syntax should the engineer use to store this value correctly?

Question 78mediummultiple choice

A network automation team stores Junos device inventory in JSON. A developer notices that the JSON file contains a field "last_updated": "2024-05-01T12:00:00Z" and wants to compare it against the current time in a Python script. Which statement correctly describes how a standard JSON parser handles this value?

Question 79hardmultiple choice

An automation engineer is building a Python script that generates Junos configuration snippets from a JSON payload. The payload contains nested objects representing interfaces, units, and addresses. The engineer uses json.loads and then accesses data['interfaces']['ge-0/0/0']['unit'][0]['family']['inet']['address'][0]['name']. Which JSON structural feature makes this nested access pattern possible?

Question 80hardmulti select

An automation engineer is comparing YAML and JSON for storing Junos device configuration data. Which TWO statements accurately describe differences between the two formats? (Choose two.)

Question 81mediummultiple choice

An automation engineer uses a Python script to pull interface statistics from a Junos device through the Junos PyEZ Table and View framework. The View definition must map the XML element <name> to the Python attribute interface_name. Which PyEZ View syntax correctly performs this mapping?

Question 82mediummultiple choice

An automation engineer uses a Python script with the PyEZ library to retrieve interface statistics from a Junos device and wants to store the results in a file that preserves data types such as integers, booleans, and null values for later processing by another tool. The engineer needs a serialization format that is compact, widely supported by APIs, and preserves these primitive types. Which format should the engineer choose?

Question 83hardmulti select

An automation engineer is designing a data model for Junos device inventory that will be serialized to JSON and consumed by multiple tools. The engineer wants to include a null value, a boolean, and a string that contains a colon and a space. Which TWO statements correctly describe JSON serialization rules that apply to this model? (Choose two.)

Question 84hardmultiple choice

An automation engineer writes a Python script that loads a YAML file containing Junos device connection parameters. The file includes a line `timeout: 30` and another line `description: 30 seconds`. The script then uses the values in a template. Which statement correctly describes how a standard YAML parser will interpret these two scalar values?

Question 85hardmultiple choice

An automation engineer writes a Python script that reads a Junos configuration exported as JSON and uses json.loads to parse it. The script then searches for a key named "interfaces". The JSON document contains two objects at the same nesting level, each with an "interfaces" key, because the configuration was merged from two sources. What will json.loads produce, and how should the script handle it?

Question 86mediummultiple choice