Application Delivery (ADX)

Setting/Changing load-balancing distribution predictor (non-dynamic) and weight of servers

by pmorrissey on ‎05-21-2009 03:23 PM - edited on ‎10-30-2013 05:43 PM by bcm1 (1,641 Views)


How to set/change the load-balancing predictors (non-dynamic) and weight of real servers



Set the predictor at the Virtual (Vip) level and set the weight at the real server level. If you enable any of the weighted methods, you must configure both the virtual and real servers involved.


Set the predictor at the VIP level

The format for setting predictor is:-

server predictor least-conn | round-robin | weighted-round-robin | weighted | enhanced-weighted | dynamic-weighted


To globally change the load-balancing method used by the ServerIron  / ADX, use the following

server predictor round-robin

To change the load-balancing method used by the ServerIron / ADX for Virtual Server (VIP) , use the following at virtual

server enhanced-weighted


Assign weight to real server(s)

Syntax: weight <weight-value>

The <weight-value > parameter specifies the real server’s weight relative to other real servers in terms of the
number of connections on the server. Each real server is assigned a weight from 0 – 65000.



For dynamic-weighted example, consult Setting/Changing the load-balancing dynamic predictor

Sample Script/Code/Configuration


server real rs1

weight 1


server real rs2

weight 2


server real rs3

weight 3


server virtual v1

server enhanced-weighted


port http
bind http rs1 http rs2 http rs3 http


Tips / Caveats

When multiple ports of a given real server are bound to the same VIP port then the default least-connection

predictor may not produce even connection distribution among these ports. Use of round-robin predictor in these cases.


Further Reading


Load Balancing Distribution Predictors with ServerIron

Server Load Balancing 101 with ServerIron

Setting/Changing the load-balancing dynamic predictor