Backend Sets for Network Load Balancers
Use backend sets to create logical entities consisting of a network load balancing policy, health check policy, and a list of backend servers for a network load balancer.
A backend set is a logical entity defined by a load balancing policy, a health check policy, and a list of backend servers. To create a backend set, you must specify a load balancing policy and health check script, and then add a list of backend servers (compute instances). A backend set must be associated with a single listener for the network load balancer to work.
You can perform the following backend set management tasks:
List the backend sets in a network load balancer.
Create a new backend set under a network load balancer.
Edit a backend set's settings.
Enable source preservation in a backend set.