PCNE Implementing Hybrid Interconnectivity Practice Question
A company is using Dedicated Interconnect to connect their on-premises network to Google Cloud. They have two VLAN attachments configured, each with a separate Cloud Router with active/active BGP. They want to ensure that traffic from their on-premises network to Google Cloud uses both attachments equally. Which configuration should they implement?
⚠ Common exam trap
It's easy for candidates to assume MED is only for influencing inbound traffic from Google Cloud to on-premises, but in this scenario, the MED values are set on the on-premises peers to influence how Google Cloud selects the return path, and equal MED is required for ECMP to work.
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
✓
Set the same MED value on both on-premises BGP peers, and ensure the AS path length is identical.
Setting the same MED (Multi-Exit Discriminator) value on both on-premises BGP peers ensures that Google Cloud's Cloud Routers, which are configured with active/active BGP, will see both paths as equally preferred. When the AS path length is also identical, the BGP best-path selection algorithm on the Cloud Routers will load-balance traffic across both VLAN attachments, achieving equal utilization. This is the standard method for enabling equal-cost multipath (ECMP) over Dedicated Interconnect with multiple attachments.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Set the same MED value on both on-premises BGP peers, and ensure the AS path length is identical.
Why this is correct
Equal MED and AS path length enables ECMP, balancing traffic across both attachments.
- ✗
Configure local preference on the Cloud Router to prefer one attachment, and rely on the other for backup.
Why it's wrong here
This only affects outbound traffic from GCP, not inbound.
- ✗
Configure a single BGP session on one Cloud Router and use static routing for the other attachment.
Why it's wrong here
This reduces redundancy and does not balance traffic.
- ✗
Set a higher MED value on one on-premises peer to deprefer that attachment.
Why it's wrong here
This would make one path less preferred, not equalize.
Visual reference
Go deeper
Related to this question
About these practice questions
Courseiva writes every PCNE question from scratch — 961 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 →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This PCNE practice question is part of Courseiva's free Google Cloud 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 PCNE exam.