Cisco Systems ISA550 Manual De Usuario

Descargar
Página de 479
Networking
Configuring the WAN
Cisco ISA500 Series Integrated Security Appliances Administration Guide
133
4
 
DNS Detection: Choose this option to detect the WAN failure by looking up 
the DNS servers that you specify in the following fields: 
-
Default DNS Servers: Send the DNS query for www.cisco.com to the 
default WAN DNS server. If the DNS server can be detected, the network 
connection is active. 
-
Specify DNS Servers: Send the DNS query for www.cisco.com to the 
specified DNS servers. Enter the IP addresses in the Primary WAN DNS 
Server
 and Secondary WAN DNS Server fields. If the primary or 
secondary DNS server can be detected, the network connection is 
active. 
STEP 2
Click Save to apply your settings.
Load Balancing with Policy-Based Routing Configuration 
Example
Use Case: A customer has two lines, one is a cable link and another is a DSL link. 
The majority of traffic goes through the cable link since it has larger bandwidth, 
and the rest traffic goes through the DSL link. As lots of secure websites (such as 
bank, or online shopping) are sensitive to flip flop the source IP address, let traffic 
for https, ftp, video, and game go through the cable link. 
Solution: Complete the following configuration tasks: 
Configure a configurable port as the secondary WAN (WAN2). See 
Connect the cable modem to the primary WAN port (WAN1) and connect 
the DSL modem to the secondary WAN port (WAN2). 
Enable the Weighted Dual WAN Settings and set the weighted value of 
WAN1 to 80% and the weighted value of WAN2 to 20%. See 
Enable the Policy-Based Routing feature and configure the Policy-Based 
Routing rules so that traffic for HTTPS, FTP, video, and game is directed to 
WAN1. See 
(Optional) Enable the Usage reports and the WAN Bandwidth reports so 
that you can view the network bandwidth usage. See 
 and