Brocade Communications Systems 12.4.00 manual Implementing the weighted site metric

1 Configuring GSLB protocol parameters

<IP address> is the IP address for which you are assigning a weight. <weight> is a value from 0 to 100. The default value is 0.

However, this command will result in an error if the IP argument for ip-weight has not been previously entered as an argument for ip-list. For example, enter the command such as the following:

SLOWANSI01(config-gslb-dns-myzone.com)#host-info www ip-weight 4.4.4.4 80

This command will respond with the error message: “IP-address not found for host-name”.

NOTE

If there is no 'ip-list' defined for the host, then the 'ip-weight' for the host IPs are removed from the 'gslb dns zone' configuration whenever the GSLB ServerIron ADX or the backend DNS servers are reloaded.

Displaying the results of traffic distribution for Weighted IPs

To view the results of traffic distribution after configuring weighted IP metrics, enter the following command.

ServerIronADX# show gslb dns zone

ZONE: gslb1.com
HOST: www:			Flashback		DNS resp.
			delay		selection
			(x100us)		counters
*	10.10.10.200: dns v-ip	ACTIVE N-AM	TCP	APP	Count (%)
			9	19	0	(0%)
*	1.1.1.101: dns v-ip	ACTIVE N-AM	0	0	4	(100%)

Syntax: show gslb dns zone

Implementing the 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, as shown in Table 5 and Table 6. In Table 5, 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.

42	ServerIron ADX Global Server Load Balancing Guide
	53-1002437-01