Brocade Communications Systems ServerIron ADX 12.4.00 Manual Manual page 188

1
Displaying GSLB information
TABLE 13
This field...
DNS override
Modify DNS response TTL
DNS TTL
DNS check interval
Remote ServerIron ADX status
update period
Session capacity threshold
Session capacity tolerance
Round trip time tolerance
Round trip time explore
percentage
Round trip time cache prefix
Round trip time cache interval
176
GSLB policy information (Continued)
Displays...
Indicates whether DNS override is enabled. DNS override replaces the
addresses in a DNS reply with the "best" address from a list of addresses you
configure. This field can have one of the following values:
•
DISABLE: The ServerIron ADX does not replace the addresses in DNS
replies with an address from a list you configure.
•
ENABLE: The ServerIron ADX replaces the addresses in DNS replies with
an address from a list you configure.
For more information about DNS override, refer to
page 33.
Indicates whether the GSLB ServerIron ADX modifies the TTL in the DNS records
in DNS responses before sending the responses to the client's DNS server. This
field can have one of the following values:
•
DISABLE: The ServerIron ADX does not modify the TTLs.
•
ENABLE: The ServerIron ADX modifies the TTLs.
Indicates the value (number of seconds) to which the GSLB ServerIron ADX
changes the TTL in each DNS record in the DNS responses before sending them
to the client's DNS server.
NOTE: If the Modify DNS response TTL field contains "DISABLE", the ServerIron
ADX does not change the TTLs, regardless of the value in this field.
Indicates how frequently the GSLB ServerIron ADX refreshes its zone and host
information with DNS servers.
Indicates how frequently the remote ServerIron ADXs send status updates to the
GSLB ServerIron ADX through the GSLB protocol.
Specifies how close to its maximum session capacity the site ServerIron ADX
(remote ServerIron ADX) can be and still be eligible as the best site for the
client. If a site ServerIron ADX exceeds the threshold, the site ServerIron ADX is
ineligible to be the best site.
Specifies the percentage by which the number of available sessions on the site
ServerIron ADX can differ from the number of available sessions on another site
ServerIron ADX and still be considered an equally good site. Refer to
ServerIron ADX's available session capacity tolerance"
Specifies the percentage by which the RTT for one site can differ from the RTT
for another site without this metric resulting in selection of one site over the
other.
Indicates the percentage of client requests from a given network for which the
GSLB ServerIron ADX intentionally ignores the RTT metric when evaluating the
IP addresses in the DNS reply. The explore percentage prevents the ServerIron
ADX from continually biasing its site selection based on the first ServerIron ADX
to return RTT information. Refer to
page 53.
Indicates the length (number of significant bits) of entries in the GSLB
ServerIron ADX's IP address cache. The prefix determines the extent to which IP
addresses are aggregated into entries in the cache.
Indicates how many seconds the GSLB ServerIron ADX keeps an unrefreshed
RTT cache entry in its cache before the entry ages out.
"Enabling DNS override"
on page 10.
"Modifying round-trip time values"
ServerIron ADX Global Server Load Balancing Guide
on
"Site
on
53-1002437-01