Free Automation and DevOps, Specialist (JN0-423) Practice Questions

Sample Practice Questions

Try these 10 sample questions from the Automation and DevOps, Specialist (JN0-423) practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1How does the Junos XML API represent the Junos configuration hierarchy?

   1. A. As XML equivalents of all configuration statements
   2. B. As JSON equivalents of operational commands only
   3. C. As text transcripts of configuration-mode sessions
   4. D. As protocol buffer messages for configuration leaves

   Answer: A

   Explanation: The guide states, "The Junos XML API defines an XML equivalent for all statements in the Junos OS configuration hierarchy". Thus configuration statements have structured XML representations; the API is not a CLI transcript, a JSON-only interface, or a protobuf model.

   Reference: Understanding the NETCONF XML Management Protocol — NETCONF and the Junos XML API Overview

2. 2Before using a data model through gNMI, which RPC discovers the models and encodings supported by the target?

   1. A. Capabilities
   2. B. Get
   3. C. Set
   4. D. Subscribe

   Answer: A

   Explanation: Juniper states, "Capabilities: Use this RPC to discover the device's capabilities, such as supported models and encodings." The other RPCs retrieve data, change configuration, or establish subscriptions.

   Reference: Understanding Dial-in Telemetry — gNMI Service — Capabilities

3. 3Which Ansible file defines the managed Junos devices and their host groups?

   1. A. The inventory file
   2. B. The module source file
   3. C. The task result file
   4. D. The configuration template

   Answer: A

   Explanation: Juniper states, "The Ansible inventory file defines the hosts and groups of hosts upon which commands, modules, and tasks in a playbook operate." Inventory supplies the managed targets rather than module implementation, results, or rendered configuration.

   Reference: Understanding the Ansible Inventory File When Managing Junos Devices — Inventory File Overview

4. 4When are enabled commit scripts invoked relative to standard Junos OS configuration validity checks?

   1. A. After the new configuration becomes active
   2. B. Only when standard validity checks fail
   3. C. After standard validity checks complete
   4. D. Before standard validity checks are performed

   Answer: D

   Explanation: Juniper states that the system invokes commit scripts "during the commit process before the standard Junos OS validity checks are performed." Script-generated configuration must therefore still pass the standard checks.

   Reference: How Commit Scripts Work — How Commit Scripts Work — opening description

5. 5What is YANG's role in managing Junos devices?

   1. A. It transports RPC messages over an encrypted session
   2. B. It executes scripts when operational events occur
   3. C. It serializes every telemetry update into binary bytes
   4. D. It models configuration, state, RPCs, and notifications

   Answer: D

   Explanation: RFC 7950 states, "YANG is a data modeling language used to model configuration data, state data, Remote Procedure Calls, and notifications for network management protocols." It describes the data and operations; it is not itself a transport, event-script runtime, or binary serializer.

   Reference: RFC 7950 — The YANG 1.1 Data Modeling Language — Abstract

6. 6Which CLI command reveals the XML RPC request corresponding to show interfaces?

   1. A. show interfaces | display set
   2. B. show interfaces | display xml rpc
   3. C. show interfaces | display json
   4. D. show interfaces | display inheritance

   Answer: B

   Explanation: The documentation instructs, "to retrieve the operational request tag for a given command, issue command | display xml rpc in the CLI." The rpc modifier reveals the request rather than merely serializing the command output.

   Reference: Understanding the NETCONF XML Management Protocol — NETCONF and the Junos XML API Overview — discovering request tags

7. 7For the Junos gNMI Get implementation documented in Understanding Dial-in Telemetry, which type value is valid for retrieving configuration?

   1. A. STATE
   2. B. CONFIG
   3. C. ALL
   4. D. OPERATIONAL

   Answer: B

   Explanation: The Junos implementation note specifies, "The valid type option is CONFIG." A protocol enum can contain additional values without the device implementation accepting them for this Get operation.

   Reference: Understanding Dial-in Telemetry — gNMI Service — Get, implementation note

8. 8In an INI inventory, which section header assigns variables to every host in the junos group?

   1. A. [junos:children]
   2. B. [junos:vars]
   3. C. [junos]
   4. D. [all:children]

   Answer: B

   Explanation: Juniper shows "[junos:vars]" followed by "ansible_connection=local". The vars suffix defines group variables; a plain group lists hosts and children defines nested groups.

   Reference: Understanding the Ansible Inventory File When Managing Junos Devices — Sample Inventory File for the juniper.device Modules

9. 9What configuration view is provided as input to a Junos commit script?

   1. A. The post-inheritance candidate configuration
   2. B. The unexpanded configuration-group definitions
   3. C. The most recent rollback configuration
   4. D. The active configuration before candidate edits

   Answer: A

   Explanation: The guide states, "The input for a commit script is the post-inheritance candidate configuration in Junos XML API format." Inherited group values have been applied and inactive portions removed; the input is not the old active or rollback configuration.

   Reference: How Commit Scripts Work — Commit Script Input

10. 10A custom nonnative YANG model extends Junos configuration syntax. What is the primary role of its required translation script?

    1. A. Map nonnative configuration to Junos syntax and add it transiently to checkout
    2. B. Map nonnative configuration to Junos syntax and permanently rewrite the candidate
    3. C. Map native Junos configuration to nonnative syntax before installing the model
    4. D. Map operational state to nonnative syntax without processing configuration

    Answer: A

    Explanation: Juniper lists two translation-script functions: "Convert the configuration data corresponding to the nonnative YANG data models into Junos OS syntax" and "Add the translated configuration data as a transient change in the checkout configuration during the commit operation". The mapping is toward native configuration and its translated output is transient, rather than a permanent candidate rewrite or an operational-state translation.

    Reference: Create Translation Scripts for YANG Configuration Models — Create Translation Scripts for YANG Configuration Models — introduction