CDN Multi-CDN Strategy & Failover 2

Question 1

Which DNS-based technique is most commonly used to distribute traffic across multiple CDN providers in a multi-CDN setup?

Accepted Answer

GeoDNS with weighted records

Answer

GeoDNS with weighted records allows traffic to be directed to different CDN providers based on geography and configured weight percentages.

Question 2

A company uses two CDNs and detects that CDN-A has a 40% cache hit rate while CDN-B has an 85% cache hit rate for the same content. What is the most likely root cause of the disparity?

Accepted Answer

CDN-A's TTL settings are configured too low

Answer

Excessively low TTL values cause content to expire quickly and force frequent origin fetches, dramatically reducing cache hit rates.

Question 3

In a multi-CDN architecture, what is the primary purpose of a real-user monitoring (RUM) system?

Accepted Answer

To collect performance data from actual end-user sessions and inform CDN routing decisions

Answer

RUM collects latency, availability, and throughput data from real users to enable intelligent, performance-based CDN traffic steering.

Question 4

Which failover trigger threshold is most appropriate for automated CDN switching in a production multi-CDN environment?

Accepted Answer

Switch after 3 consecutive failed health checks within a 60-second window

Answer

Requiring multiple consecutive failures within a time window prevents false-positive failovers caused by transient network blips.

Question 5

A media company streams live video using two CDNs. During a failover event, viewers experience a 10-second buffering delay. Which architecture change would best minimize this delay?

Accepted Answer

Pre-warm the secondary CDN by pushing manifest and segment requests before failover

Answer

Pre-warming the secondary CDN ensures popular content is already cached, so when traffic shifts, the CDN can serve segments immediately without origin fetches.

(CDN) Content Delivery Network Certification Practice Test

(CDN) Content Delivery Network Certification Practice Test

CDN Multi-CDN Strategy & Failover 2