Brocade Communications Systems ServerIron ADX 12.4.00 - Manual (Page 223)

ServerIron ADX Global Server Load Balancing Guide 211
53-1002437-01
Advanced GSLB configuration for IPv6
2
The command results in an “IP-address not found for host-name” error if the IPv6 address
specified for the ip-weight parameter was not used as an argument when you defined the IP list.
For information about specifying IP lists, see
“Specifying DNS override IP lists” on page 199.
NOTE
If no IP list is defined for the host, the IP weight for the host IPs are removed from the GSLB DNS
zone configuration whenever the GSLB ServerIron ADX reloads.
Use the show gslb dns command to view information about the distribution of traffic after the
configuration of weighted IP metrics. For more informaiton see
“Displaying DNS zone and hosts” on
page 237.
Weighted site metric
You can configure the ServerIron ADX to distribute SLB traffic among GSLB sites based on weights
configured for the sites. The weights determine the percentage of traffic each site will receive in
comparison with other sites, which may or may not have weights.
NOTE
You cannot use the weighted site metric if the weighted IP metric is enabled. You assign weights to
GSLB sites. Each GSLB site may consist of one or more ServerIron ADXs, but the weight is applicable
to the site as a whole.
The GSLB ServerIron ADX uses relative percentages in order to achieve 100% total weight
distribution.
You can configure the ServerIron ADX to distribute SLB traffic among GSLB sites based on weights
configured for the sites. The weights determine the percentage of traffic each site will receive in
comparison with other sites, which may or may not have weights.
The GSLB ServerIron ADX uses relative percentages in order to achieve 100% total weight
distribution, as shown in
Table 19 and Table 20 . In Table 19 , the total of the Configured weighted
site metrics (second column) is 100. The last column shows that the GSLB ServerIron ADX
distributes the traffic to the IP addresses exactly as configured. In this example, traffic distribution
is straightforward because the total weight of all three GSLB sites equals 100.
Now consider the example in Table 20 . In this example, the total of the configured weighted site
metrics (second column) does not equal 100. However, as illustrated in the last column, the GSLB
ServerIron ADX uses relative percentages in order to achieve 100% total weight distribution.
TABLE 19 Example weighted site metric configuration
GSLB site Configured weighted site metric Relative weighted site metric
San Jose 50 50%
New York 30 30%
London 20 20%
Total 100 100%