mediumMultiple Choice
350-401 Practice Question: Given this telemetry configuration on a Cisco…
Given this telemetry configuration on a Cisco IOS-XE device:
telemetry ietf subscription 400 encoding encode-kvgpb filter xpath /interfaces/interface/state stream yang-push update-policy periodic 1000 receiver ip address 10.1.1.1 50000 protocol grpc source-interface Loopback0
What is the effect of the source-interface Loopback0 command?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
It uses the IP address of Loopback0 as the source for telemetry packets to the receiver.
The source-interface command ensures that all telemetry packets sent to the receiver use the IP address of Loopback0 as the source.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
It forces the telemetry receiver to listen on Loopback0.
Why it's wrong here
The receiver's IP and port (10.1.1.1 50000) are configured separately, so Loopback0 cannot make the collector listen there. The command sets the source address of outgoing gRPC packets, which is its actual purpose — useful when the collector filters by sender address or multiple paths exist.
- ✓
It uses the IP address of Loopback0 as the source for telemetry packets to the receiver.
Why this is correct
Loopback0's IP address becomes the source address in the telemetry packet headers, ensuring the gRPC receiver sees a stable, routable source rather than a transient physical interface address. This satisfies the need for deterministic telemetry source identification.
- ✗
It restricts the telemetry data to only Loopback0 interface counters.
Why it's wrong here
Data scope comes from the xpath filter (/interfaces/interface/state), which already covers all interfaces; source-interface does not narrow it. The command only sets the local IP address for the outbound gRPC session, and is correct when the collector must see a consistent, routable source address.
- ✗
It changes the update policy to on-change for Loopback0.
Why it's wrong here
Update policy is defined by the separate 'update-policy periodic 1000' line, which this command does not touch. Source-interface only selects the local address used for the gRPC connection, so it would be the right choice when you need telemetry packets to originate from a stable, routable address.
Go deeper
Related to this question
About these practice questions
Courseiva writes every 350-401 question from scratch — 1,923 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
Same concept, more angles
1 more way this is tested on 350-401
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. An engineer configures gRPC dial-out telemetry on a Cisco IOS-XE device: ``` telemetry ietf subscription 100 receiver ip address 10.1.1.100 port 50051 protocol grpc-tcp source-address 10.1.1.1 encoding encode-kvgpb filter xpath /interfaces/interface/state/counters update-policy periodic 10000 ``` What is the purpose of the 'source-address' command?
medium- A.It specifies the IP address of the telemetry receiver.
- ✓ B.It specifies the source IP address for the telemetry stream.
- C.It enables the device to receive telemetry data from the receiver.
- D.It specifies the IP address of the network management station.
Why B: The 'source-address' command specifies the IP address that the device uses as the source IP when sending telemetry data to the receiver. This ensures that the receiver can identify the device and that the traffic is sourced from a specific interface.
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 350-401 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 350-401 exam.