Brocade Communications Systems 12.4.00 Configuring Gslb protocol parameters Gslb policy metrics

		Configuring GSLB protocol parameters		1
TABLE 2	GSLB policy metrics
Metric		Default	Configuration options
Server (host) health		Enabled.	You can disable this metric.
		The GSLB ServerIron ADX performs	NOTE: When both the health check
		Layer 4 health checks on the TCP or	metric and the Flashback
		UDP port and Layer 7 health checks	metric are disabled, the
		on the application, if the application	ServerIron ADX does not
		is known to the ServerIron ADX.	perform any Layer 4 or Layer
		NOTE: If all the sites fail their health	7 health checks.
		checks, resulting in all the
		sites being rejected by the
		GSLB ServerIron ADX, the

ServerIron ADX sends the DNS reply unchanged to the client.

Weighted IP metric	Disabled.
	When enabled, the ServerIron ADX
	distributes GSLB traffic among IP
	addresses in a DNS reply, based on
	weights assigned to the IP
	addresses.

You can enable this metric and assign weights to individual IP addresses. The weight can be from 0 to 100. The default is 0.

You can disable this metric.

Weighted site metric	Disabled.
	When the weighted IP metric is
	enabled, the weighted site metric is
	disabled. The weighted site metric is
	an alternative to the weighted IP
	metric. They are mutually exclusive.
	When enabled, the ServerIron ADX
	distributes SLB traffic among GSLB
	sites based on weights configured
	for the sites.

You can enable this metric and assign weights to individual sites. The weight can be from 0 to 100. The default is 0.

You can disable this metric.

Session capacity threshold	Enabled.
	The default value for the threshold is
	90%. Thus a site ServerIron ADX is
	eligible to be the best site only if its
	session utilization is below 90%.

You can change the threshold to a value from 0-100%.

You can disable this metric.

Active bindings metric	Disabled.
	When enabled, the ServerIron ADX
	selects an IP address with the
	highest number of active bindings
	as the best IP address for the client.

You can enable and disable this metric.

Round-trip time (RTT) from remote ServerIron ADXs to the DNS clients.

Enabled.

The default RTT cache interval is 120 seconds.

The default cache prefix length is 20 bits.

The default tolerance (used when comparing otherwise equal sites) is 10%.

The default explore percentage is 5%.

You can change the RTT cache interval, cache prefix length, tolerance, and explore percentage individually.

You can disable this metric. If you disable RTT, the GSLB ServerIron ADX instructs the site ServerIron ADXs to stop sending RTT information.

Geographic location Enabled. You can disable this metric.

ServerIron ADX Global Server Load Balancing Guide	35
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