Load Balancer Overview

What is a Load Balancer?

A load balancer is a device that distributes network or application traffic across a cluster of servers. Load balancing improves responsiveness and increases the availability of applications.  Furthermore, Hostwinds load balancers are a service that occupies a neutron network port and is assigned a dedicated IP for each load balancer created.

Diagram

Keywords

Listener

A listener is created by the user to listen on specific ports assigned by the user. Load balancers can have multiple listeners, but ports can only be assigned to one listener.

i.e., You can have 2 listeners who listen to Port 80 and Port 443, but not 2 listeners listening to port 80.

Member

Members are the servers that the load balancer serves traffic to through the use of listeners.

Each member is assigned an IP address and the port that it uses to serve traffic to.

Health Monitor

Health monitors are used for monitoring the members. If one becomes unavailable, traffic will be served to an online member if available.

Pool

Pools hold lists of members that serve content through the load balancer.