Chapter 8 WAN and 3G Screens
ZyWALL 2WG User’s Guide
176
To load balance using the weighted round robin method, select
Weighted Round Robin
in the
Load Balancing Algorithm
field.
Figure 112
Load Balancing: Weighted Round Robin
The following table describes the related fields in this screen.
8.2.2.5 Spillover
With the spillover load balancing algorithm, the ZyWALL sends network traffic to the primary
interface until the maximum allowable load is reached, then the ZyWALL sends the excess
network traffic of new sessions to the secondary WAN interface. Configure the
Route
Priority
metrics in the
WAN General
screen to determine the primary and secondary WANs.
In cases where the primary WAN interface uses an unlimited access Internet connection and
the secondary WAN uses a per-use timed access plan, the ZyWALL will only use the
secondary WAN interface when the traffic load reaches the upper threshold on the primary
WAN interface. This allows you to fully utilize the bandwidth of the primary WAN interface
while avoiding overloading it and reducing Internet connection fees at the same time.
In the following example figure, the upper threshold of the primary WAN interface is set to
800K. The ZyWALL sends network traffic of a new session that exceeds this limit to the
secondary WAN interface.
Table 35
Load Balancing: Weighted Round Robin
LABEL
DESCRIPTION
Active/Active
Mode
Select
Active/Active Mode
and set the related fields to enable load balancing on the
ZyWALL.
Load Balancing
Algorithm
Set the load balancing method to
Weighted Round Robin
.
WAN Interface
to Local Host
Mapping
Timeout
Select this option to have the ZyWALL send all of a local computer’s traffic through
the same WAN interface for the period of time that you specify (1 to 600 seconds).
This is useful when a redirect server forwards a local user’s request for a file and
informs the file server that a particular WAN IP address is requesting the file. If the
user’s subsequent sessions came from a different WAN IP address, the file server
would deny the request.
Interface
This field displays the name of the WAN interface (
WAN 1
and
WAN 2
).
Ratio
Specify the weight for the interface. Enter 0 to set the ZyWALL not to send traffic load
to the interface. The higher the number, the bigger the weight (the more traffic sent).