Cross-Zone Load Balancing Overview

Questions and Answers

Traffic is distributed only in its Availability Zone.

Traffic is distributed across all registered targets in all enabled Availability Zones. (correct)

Traffic is equally distributed among the load balancer nodes.

Traffic is distributed solely to the targets in the lowest traffic zone.

Application Load Balancers (correct)

Network Load Balancers

Classic Load Balancers

Gateway Load Balancers (correct)

Equally across all connected load balancer nodes.

Equally, regardless of the number of targets.

Only through the primary Availability Zone.

Based on the number of registered targets in each zone. (correct)

16.6% Signup and view all the answers

25% Signup and view all the answers

They have cross-zone load balancing disabled by default. Signup and view all the answers

To evenly distribute traffic across all zones for performance. Signup and view all the answers

Distributes traffic only within its own Availability Zone. Signup and view all the answers

Study Notes

Cross-zone load balancing allows load balancer nodes to distribute traffic across all registered targets in enabled Availability Zones.
When disabled, traffic distribution is limited to targets in the same Availability Zone as the load balancer node.

Cross-zone load balancing is always enabled for Application Load Balancers, ensuring even traffic distribution.

For Network Load Balancers and Gateway Load Balancers, cross-zone load balancing is disabled by default, requiring manual activation for broader traffic distribution.

In a scenario with cross-zone load balancing disabled:
- Each of the three targets in Availability Zone A receives 16.6% of total traffic.
- Each of the two targets in Availability Zone B receives 25% of total traffic, leading to imbalanced traffic if zones have unequal targets.

When cross-zone load balancing is enabled, traffic is distributed more evenly across all available targets in all enabled Availability Zones, improving overall resource utilization.