JNCIA-DevOps NETCONF And XML API Practice Test 2 — 15 Questions

Question 1

Which command or tool on a Junos device verifies that the NETCONF subsystem is enabled and listening for SSH connections?

Accepted Answer

show system services netconf ssh. NETCONF over SSH runs as a subsystem on Junos and can be verified via system services configuration or operational commands.

Answer

show netconf settings

Answer

show xml-api status

Answer

show netconf status connections

Question 2

When executing a NETCONF request, you specify but omit any filtering tags. What is returned in the ?

Accepted Answer

The complete configuration contained within the candidate datastore.. Omiting filter tags on a <get-config> request returns the entire contents of the specified configuration datastore.

Answer

An rpc-error stating that a filter is mandatory.

Answer

Only the differences between candidate and running configurations.

Answer

Only the top-level system hierarchy statements.

Question 3

In Junos XML API, what is the XML namespace associated with Junos-specific RPCs and operational tags?

Accepted Answer

http://xml.juniper.net/junos/*/junos-rpc. Junos XML API elements use specific namespaces like http://xml.juniper.net/junos/12.1X46/junos-sw for software or general rpc namespaces.

Answer

http://www.cisco.com/ns/yang/cisco-se

Answer

urn:juniper:params:xml:ns:netconf:base:1.0

Answer

urn:ietf:params:xml:ns:netconf:base:1.0

Question 4

Which tool or library is commonly used in Python to simplify interacting with Junos NETCONF APIs by abstracting low-level XML handling?

Accepted Answer

Junos PyEZ (juniper-eznc). PyEZ is Juniper's official Python library designed specifically for interacting with Junos devices via NETCONF.

Answer

Netmiko

Answer

Paramiko

Answer

Requests

Question 5

You need to load a set of configuration changes into the Junos candidate datastore from an inline XML string using NETCONF. Which RPC element is used to load configuration data?

Accepted Answer

. The RPC is a Juniper-specific extension used within NETCONF to load configuration data with formats like XML, text, or set.

Answer

<update-candidate>

Answer

<set-config>

Answer

<edit-config>

Question 6

An automation script performs a NETCONF transaction that triggers an alarm. You want to retrieve current system alarms using the Junos XML API. Which RPC tag represents this request?

Accepted Answer

. The RPC retrieves active system alarms from the Junos device.

Answer

<retrieve-alarms>

Answer

<get-system-alarms>

Answer

<get-chassis-alarms>

Question 7

You are configuring NETCONF traceoptions on a Junos device to debug an XML parsing issue. Which configuration statement enables logging of all NETCONF protocol messages to a file named 'netconf-debug.log'?

Accepted Answer

set system services netconf traceoptions file netconf-debug.log
set system services netconf traceoptions flag all. Traceoptions under the netconf system services hierarchy control logging of NETCONF traffic.

Answer

set protocols netconf traceoptions file netconf-debug.log flag detail

Answer

set security netconf logging file netconf-debug.log

Answer

set system netconf trace file netconf-debug.log level debug

Question 8

When you issue a NETCONF <get-config> request for the running configuration, why might the request fail or return empty on certain Junos platforms?

Accepted Answer

The <running/> datastore capability is supported, but explicit locking rules or device state might restrict it if unsupported parameters are sent.. In standard NETCONF (RFC 6241), the running datastore must be supported, but Junos requires candidate configuration usage for edits; however, running is supported for reading. If it fails, it is often due to datastore capability support.

Answer

Running configuration can only be accessed using CLI commands, never NETCONF.

Answer

The <running/> tag must always be accompanied by a password attribute.

Answer

Junos does not support reading the running configuration datastore via NETCONF.

Question 9

What is the purpose of the <hello> element exchanged immediately after establishing a NETCONF SSH session?

Accepted Answer

To exchange supported protocol capabilities and namespace identifiers.. The <hello> element is used by both client and server to exchange supported capabilities and session parameters.

Answer

To authenticate the SSH username and password.

Answer

To request an immediate reboot of the Junos routing engine.

Answer

To lock the candidate configuration database automatically.

Question 10

An automation script executes a NETCONF <get-config> query with a specific subtree filter for interface statistics. However, the response contains configuration data instead of operational statistics. Why did this occur?

Accepted Answer

The RPC targets configuration datastores, whereas interface statistics are operational state data retrieved via the RPC.. retrieves configuration data, whereas operational statistics require the RPC with operational filters.

Answer

The session was not locked prior to executing the query.

Answer

Interface statistics cannot be retrieved via NETCONF; CLI parsing is required.

Answer

The subtree filter syntax was invalid, causing the device to fallback to the default configuration view.

Question 11

You send an edit-config RPC with an invalid XML tag name. What is the standard structure of the error returned in the <rpc-reply>?

Accepted Answer

An element containing diagnostic sub-elements like and .. NETCONF errors are returned inside an element containing details such as error-type, error-tag, and error-message.

Answer

A standard Linux kernel panic log string.

Answer

An HTTP 400 Bad Request status code.

Answer

A syslog message printed directly to the terminal emulator.

Question 12

What is the role of the <rpc> element in a NETCONF message exchange?

Accepted Answer

It acts as a wrapper enclosing the specific NETCONF method request sent by the client to the server.. The <rpc> element is the protocol envelope used by the client to send a request to the NETCONF server.

Answer

It defines the security credentials for SSH authentication.

Answer

It stores error logs returned by the Junos routing engine.

Answer

It terminates the NETCONF session upon completion.

Question 13

You need to execute a Junos CLI command (such as 'show version') as an XML RPC request via NETCONF. Which RPC tag encapsulates raw Junos CLI operational commands?

Accepted Answer

show version. The tag allows executing arbitrary operational CLI commands formatted as text within the Junos XML API.

Answer

show version

Answer

show version

Answer

show version

Question 14

Which Junos configuration statement enables the NETCONF service over SSH for remote automation clients?

Accepted Answer

set system services netconf ssh. Enabling NETCONF on Junos requires configuring the system services netconf ssh hierarchy.

Answer

set protocols netconf enable

Answer

set netconf ssh-server enable

Answer

set system xml-api netconf enable

Question 15

When using NETCONF to edit a Junos configuration, you include the attribute operation="create" on an existing configuration leaf. What behavior does the device exhibit?

Accepted Answer

The device returns an rpc-error indicating that the target data model element already exists.. The 'create' operation adds a configuration node only if it does not already exist; if it exists, it returns an error.

Answer

The attribute is ignored, and the operation defaults to merge.

Answer

The configuration value is updated successfully.

Answer

The existing node is deleted and recreated with the new value.