Juniper JN0-423 問題練習

Question No : 1
A network automation system needs to modify a Junos configuration path through a model-driven gNMI interface.
Which gNMI operation should be used?

• A.Subscribe
• B.Get
• C.Set
• D.Poll

答えを確認する

正解:
Explanation:
gNMI Set is used to update, replace, or delete configuration data. Get retrieves data, and Subscribe receives telemetry updates.

Question No : 2
An Ansible playbook renders Junos interface configuration from a Jinja2 template. Interface names are correct, but VLAN IDs are wrong for one site.
What should the engineer check first?

• A.The gRPC service definition
• B.The site-specific host_vars or group_vars
• C.The Grafana dashboard query
• D.The SNMP script output

答えを確認する

正解:
Explanation:
Jinja2 templates render values from variables. If only one site has incorrect values, the likely issue is in that site's host_vars or group_vars.

Question No : 3
A Junos device should automatically collect diagnostic output when a routing adjacency goes down. The action should be triggered by the system event, not by a manual operator command or a configuration commit.
Which combination best fits this requirement?

• A.Event policy and event script
• B.Commit script and commit check
• C.Op script and manual CLI execution
• D.SNMP script and inventory group

答えを確認する

正解:
Explanation:
An event policy can match a system event and trigger an event script. This is appropriate for automated responses to operational events.

Question No : 4
A multi-vendor automation platform needs to collect BGP state from Junos and non-Junos devices using a consistent model-driven schema.
Which model family best supports this requirement?

• A.Junos event policy
• B.OpenConfig
• C.Ansible inventory
• D.JSNAPy operator

答えを確認する

正解:
Explanation:
OpenConfig provides vendor-neutral YANG models for configuration and operational state, making it useful for multi-vendor automation.

Question No : 5
A Junos telemetry pipeline uses Telegraf to collect metrics and InfluxDB to store time-series data. Operations teams need dashboards to visualize the collected telemetry.
Which component provides the dashboard function in the TIG stack?

• A.Telegraf
• B.InfluxDB
• C.gNMIc
• D.Grafana

答えを確認する

正解:
Explanation:
In the TIG stack, Telegraf collects metrics, InfluxDB stores time-series data, and Grafana provides visualization dashboards.

Question No : 6
A YANG model contains the following simplified structure:
container interfaces {
list interface {
key "name";
leaf name {
type string;
}
}
}
What does the key "name" statement indicate?

• A.The name leaf uniquely identifies each list entry
• B.The name leaf stores the telemetry sample interval
• C.The name leaf imports another YANG module
• D.The name leaf encrypts interface configuration

答えを確認する

正解:
Explanation:
In a YANG list, the key statement identifies which leaf or leaves uniquely identify each entry in the list.

Question No : 7
An Ansible project stores Junos login credentials in variable files. The team wants these values encrypted in the repository but still available to playbooks during execution.
Which feature should be used?

• A.Jinja2 template
• B.JSNAPy test file
• C.Ansible Vault
• D.OpenConfig model

答えを確認する

正解:
Explanation:
Ansible Vault encrypts sensitive variables such as passwords, tokens, and keys while allowing playbooks to access them after decryption.

Question No : 8
A Junos administrator wants to enforce a rule that every firewall filter must include a required logging term. If the term is missing, the configuration must be rejected before becoming active.
Which script type should be used?

• A.Event script
• B.Commit script
• C.Op script
• D.SNMP script

答えを確認する

正解:
Explanation:
Commit scripts run during commit processing and can validate the candidate configuration. They can reject commits that do not meet required standards.

Question No : 9
An engineer uses gNMIc to retrieve the current value of a Junos interface counter one time. The engineer does not want continuous updates or a long-running telemetry stream.
Which gNMI operation should be used?

• A.Get
• B.Set
• C.Subscribe
• D.Commit

答えを確認する

正解:
Explanation:
gNMI Get retrieves current configuration or operational state values. Subscribe is used for continuous or streaming telemetry updates.

Question No : 10
A network automation team uses Terraform with a Juniper-related provider to manage network infrastructure resources. Before applying any changes, the team wants to see which resources Terraform will create, update, or delete.
Which command should be used?

• A.terraform apply
• B.terraform destroy
• C.terraform fmt
• D.terraform plan

答えを確認する

正解:
Explanation:
terraform plan previews the changes Terraform will make before applying them. This is useful in network automation workflows to review intended infrastructure changes safely.

Question No : 11
A YANG model contains an interface configuration node that stores a single IP address value.
Which YANG construct should this node most likely be?

• A.container
• B.list
• C.leaf
• D.grouping

答えを確認する

正解:
Explanation:
A leaf represents a single value in a YANG data tree, such as an IP address, string, integer, or boolean.
JN0-423 High-Fidelity Practice Questions - Refined Set 3

Question No : 12
A Junos administrator wants to enforce interface naming standards whenever an engineer commits a configuration change. Noncompliant configuration should be rejected before activation.
Which mechanism should be used?

• A.Commit script
• B.Op script
• C.SNMP script
• D.gNMI Subscribe

答えを確認する

正解:
Explanation:
Commit scripts validate candidate configuration during commit processing and can reject configurations that violate standards.

Question No : 13
A Junos telemetry subscription should send interface counter updates every 30 seconds, even if the counter values have not changed.
Which gNMI subscription mode should be used?

• A.ON_CHANGE
• B.ONCE
• C.POLL
• D.SAMPLE

答えを確認する

正解:
Explanation:
SAMPLE mode sends updates at a configured interval. ON_CHANGE sends updates only when values change.

Question No : 14
A developer chooses Protocol Buffers for a gRPC-based automation interface instead of plain text message formats.
Which characteristic explains this choice?

• A.They are used only for CLI screen scraping
• B.They provide efficient serialization and strongly typed messages
• C.They replace all YANG models in telemetry systems
• D.They are required only for Ansible Vault encryption

答えを確認する

正解:
Explanation:
Protocol Buffers provide compact serialization and strongly typed message definitions, which makes them suitable for gRPC APIs.

Question No : 15
An Ansible workflow deploys Junos configuration successfully. The team now wants an automated method to confirm that expected operational values exist after deployment.
Which addition best satisfies this requirement?

• A.Store the playbook in a different inventory group
• B.Replace Jinja2 templates with static files
• C.Add JSNAPy validation tests
• D.Convert Vault variables into Protocol Buffers

答えを確認する

正解:
Explanation:
JSNAPy tests validate Junos operational state and are useful for post-change verification after configuration deployment.