Weighted Round Robin Distribution Algorithm - Alcatel-Lucent OmniSwitch 9900 Series Network Configuration Manual

Configuring Server Load Balancing

Weighted Round Robin Distribution Algorithm

In order to distribute traffic among operating servers, the SLB cluster must have a method of selecting a
server among a pool (cluster) of operating servers ("in service" mode) depending on some criteria. This
method is commonly called the SLB cluster distribution algorithm.
The distribution algorithm on an OmniSwitch is weighted round robin, where the SLB cluster distributes
traffic according to the relative "weight" a server has within an SLB cluster. In the figure below, for
example, Server A has been assigned by the network administrator a relative weight of 30, which is the
largest weight in the SLB cluster called "WorldWideWeb." Server A handles twice as much traffic as
Server C (which has a weight of 15), three times the traffic of Server D (which has a weight of 10), and six
times the traffic of Server B (which has a weight of 5).
Server A
IP: 128.241.130.107
Loopback Address:
128.241.130.204
Note. See "Modifying the Relative Weight of a Physical Server" on page 24-15
modifying the relative weights of servers in an SLB cluster.
OmniSwitch AOS Release 8 Network Configuration Guide
SLB CLuster "WorldWideWeb"
VIP: 128.241.130.204
Server B Server C
IP: 128.241.130.109 IP: 128.241.130.115
Loopback Address: Loopback Address:
128.241.130.204
OmniSwitch 7800
Switch
Weighted Round Robin Algorithm
December 2017
Server Load Balancing Overview
Server D
IP: 128.241.130.135
Loopback Address:
128.241.130.204 128.241.130.204
Server A handles twice the traffic of Server C,
three times the traffic of Server D, and six
times the traffic of Server B.
for information on
page 24-8