Technical data

ServerIron ADX Advanced Server Load Balancing Guide 103
53-1002435-03
Sample configurations
2
• If the cache server is unavailable or does not have the page and thus attempts to send the
request back through the ServerIron ADX to the Internet, the ServerIron ADX sends the request
to the router for forwarding to the Internet. If the virtual IP address is not configured on the
ServerIron ADX, the ServerIron ADX drops the request from the cache server.
Figure 24 shows an example of a configuration that requires CFO.
FIGURE 24 Configuration using policy-based Cache Failover (CFO)
Here are the CLI commands for adding a virtual IP address to a cache group. Add the virtual IP
address to which your router forwards the clients’ HTTP requests.
ServerIronADX(config)# ip policy 1 cache tcp 80 global
ServerIronADX(config)# server cache-group 1
ServerIronADX(config-tc-1)# virtual-ip 209.157.22.77
Syntax: [no] virtual-ip { <ipv4_address> | <ipv6_address> }
The <ipv4_address> variable specifies an IPv4 address for the virtual IP address of the cache
group. An IPv4 virtual IP address can only be configured under an IPv4 cache group.
Internet
www.stockquotes.com
1.0.0.2
www.oldnews.com
1.0.0.1
www.livenews.com
1.0.0.3
Web servers
Border Access
Router (BAR)
e18 (output port)
e17
Remote Access
Server (RAS)
Web Queries
208.95.6.3
208.95.7.3
208.95.8.3
Cache server3
209.157.22.205
Cache server4
209.157.22.215
Cache server5
209.157.22.225
Cache group 1,
Virtual IP address 209.147.22.77
SI
The router has a policy that
forwards HTTP requests to
a virtual IP address.
To enable the ServerIron to
properly forward the requests,
add the virtual IP address to
the cache group.