Networking
Configuring the WAN
Cisco ISA500 Series Integrated Security Appliances Administration Guide 130
4
Configuring WAN Redundancy
If you have two ISP links, one for WAN1 and another for WAN2, use the
Networking > WAN Redundancy pages to configure the WAN redundancy to
determine how the two ISP links are used. Refer to the following topics:
Dual WAN Settings, page130
Load Balancing with Policy-Based Routing C onfiguration Example,
page133
NOTE Before you configure the WAN redundancy settings, you must first configure the
secondary WAN connection. See Configure a secondary WAN, page 125.
NOTE When the security appliance is working in the Dual WAN Settings or Failover mode,
if one WAN link is down such as the cable is disconnected, the WAN redundancy
and Policy-Based Routing settings are ignored and all traffic is handled by the
active WAN port.
Dual WAN Settings
Use the Networking > WAN Redundancy > Dual WAN Settings page to segregate
traffic between links that are not of the same speed. For example, you can bind the
high-volume services through the port that is connected to a high speed link, and
bind the low-volume services to the port that is connected to the slower link.
Load balancing is implemented for outgoing traffic and not for incoming traffic. To
maintain better control of WAN port traffic, consider making the WAN port Internet
address public and keeping the other one private.
NOTE To configure load balancing, make sure that you configure both WAN ports to keep
alive. If the WAN port is configured to time out after a specified period of inactivity,
then load balancing is not applicable.
STEP 1 Choose an option in the Dual WAN Settings section to specify how the two ISP
links are used. The two links will carry data for the protocols that are bound to
them.
Weighted Dual WAN Settings: Distributes the bandwidth to two WAN ports
by the weighted percentage or by the weighted link bandwidth. If you
choose this mode, choose one of the following options and finish the
settings:
-Weighted b y Percentag e: If you choose this option, specify the
percentage for each WAN, such as 80% bandwidth for WAN1 and at least
20% bandwidth for WAN2.