Configures the ServerIron to prefer an IP address with the highest number of active bindings.

Active bindings are a measure of the number of active real servers bound to a Virtual IP address (VIP) residing on a GSLB site. The GSLB ServerIron uses the Active Bindings metric to select the best IP address for the client. The VIP with the highest number of active bindings is the IP address preferred by the Active Bindings metric.

EXAMPLE:

To configure the Active Bindings metric, enter the following command:

SLB-ServerIron(config-gslb-policy)# active-bindings

Syntax: [no] active-bindings

Possible values: N/A

Default value: Disabled

Disables or re-enables the capacity threshold GSLB metric. This metric represents a site ServerIron’s available TCP/UDP session capacity. This metric is enabled by default, which means the GSLB ServerIron uses this metric when evaluating the sites in a DNS reply to choose the best site.

EXAMPLE:

To disable this metric, enter the following command:

ServerIron(config-gslb-policy)# no capacity

To re-enable this metric, enter the following command:

ServerIron(config-gslb-policy)# capacity

Syntax: [no] capacity

Possible values: N/A

Default value: Enabled

Changes the number of sampling intervals and the sampling rate for the connection-load metric.

By default, the site ServerIron samples the load of new connections every five seconds and stores the average connection load for five intervals: the average loads at the previous 5, 10, 15, 20, and 25 seconds.

EXAMPLE:

ServerIron(config-gslb-policy)# connection-load intervals 6 5

This command changes the number of sampling intervals from 5 to 6 but leaves the sample rate set to 5 seconds. At any given time, the site ServerIron will have the average load for six intervals, for the previous 5, 10, 15, 20, 25, and 30 seconds. The average connection load will be calculated based on these six samples.

Syntax: [no] connection-load intervals <num-intervals> <sampling-rate>

The <num-intervals> parameter specifies the number of samples you want the site ServerIron to collect and average together. You can specify 1 – 8 intervals. The default is 5.

The <sampling-rate> parameter specifies the number of seconds between each sample. You can specify 1 – 60 seconds. The default is 5 seconds.

Possible values: 1 – 8 intervals; 1 – 60 seconds

Default value: 5 intervals; 5 seconds

Enables the site connection-limit metric and specifies the connection limit for the site.

EXAMPLE:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# connection-load limit 500

This command sets the site connection limit to 500 connections. During site comparison, the GSLB policy discards sites that have an average load of new connections that is higher than the amount you specify. All other sites are passed to the next GSLB policy metric as potential candidates.

Syntax: [no] connection-load limit <average-load>

Possible values: 1 – as high a value as you need

Default value: no default

Changes the relative weights of the data samples used by the connection-laod metric.

By default, the site ServerIron weighs each data sample equally when calculating the connection average for the GSLB policy. The weight of each interval is 1.

You can change the weights to give more emphasis to some intervals and less emphasis to others. For example, if you are using five intervals, all five have equal influence on the average load calculated by the GSLB policy. If you want to give more emphasis to the third interval, you can give the third interval a higher weight than the other intervals. To ignore an interval when calculating the average, assign the weight 0 (zero) to the interval.

EXAMPLE:

To change sample weights, enter a command such as the following at the GSLB policy level of the CLI:

ServerIron(config-gslb-policy)# connection-load weights 1 1 3 1 1

This command gives more weight to the third sampling interval than to the other intervals, while including all intervals in the calculation of the average connection load.

Syntax: [no] connection-load weights <weight1> [<weight2>...<weight8>]

The <weight> parameters specify the weights. You can specify from 0 – 10. If you enter 0, the interval is not included when calculating the average load. Enter the weights in the same order as the sampling intervals.

You do not need to enter weight values for all the intervals once you enter the last non-zero weight. For example, if you want to set the weight for interval three to 1 but use 0 for the weights of all the other intervals, you can enter the following command:

ServerIron(config-gslb-policy)# connection-load weights 0 0 1

When this command is entered, the weights for the fourth interval and higher are set to 0.

Possible values: 0 – 10

Default value: 1

Specifies how close to the maximum session capacity the site ServerIron (remote ServerIron) can be and still be eligible as the best site for the client. This mechanism provides a way to shift load away from a site before the site becomes congested. The default value for the threshold is 90%. Thus a site ServerIron is eligible to be the best site only if its session utilization is below 90%.

EXAMPLE:

To change the session-table capacity metric, enter commands such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# capacity threshold 99

Syntax: [no] capacity threshold <num>

The <num> parameter specifies the maximum percentage of a site ServerIron’s session table that can be in use. If the ServerIron’s session table utilization if greater than the specified percentage, the GSLB ServerIron prefers other sites over this site. You can specify a percentage from 0 – 100. The default is 90.

Possible values: 0 – 100

Default value: 90

Configures the ServerIron to remove IP addresses from DNS replies when those addresses fail a health check. The ServerIron removes the addresses that fail the check so long as the DNS query still contains at least one address that passes the health check.

EXAMPLE:

To configure the ServerIron to remove IP addresses from DNS replies when those addresses fail a health check, enter the following commands.

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# dns active-only

Syntax: [no] dns active-only

Possible values: N/A

Default value: Disabled

Enables the ServerIron to act as a proxy for a DNS server, by responding directly to the client queries without forwarding them to the DNS server. Just as in the regular GSLB mode, the ServerIron periodically queries the authoritative DNS server for IP addresses corresponding to the domains configured for GSLB and caches them. However, unlike regular GSLB, the ServerIron does not forward every client query to the authoritative DNS server, it responds directly to the client using the cached address list for the requested domain.

EXAMPLE:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# dns cache-proxy

Syntax: [no] dns cache-proxy

Possible values: N/A

Default value: Disabled

Changes the refresh interval for DNS queries to refresh verify zone and host information. The GSLB ServerIron sends the queries to the DNS for which it is configured to be a proxy.

EXAMPLE:

To change the refresh interval, enter commands such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# dns check-interval 50

Syntax: [no] dns check-interval <num>

The <num> parameter specifies the interval and can be from 0 – 1000000000 seconds. The default is 30 seconds.

Possible values: 0 – 1000000000 seconds

Default value: 30 seconds

This command enables the ServerIron to apply GSLB to CNAME records.

A Canonical Name (CNAME) record is a DNS record that maps an alias for a zone and application to another zone and application name in an Address record. Here is an example:

Alias	Actual name
www1.foundrynet.com	www.foundrynet.com

This CNAME record maps "www1.foundrynet.com" to "www.foundrynet.com". Another DNS Address record maps the actual name, "www.foundrynet.com", to its IP address.

By default, the ServerIron applies the GSLB policy only to zone and application names that are configured on the ServerIron. Thus, if the ServerIron receives a DNS reply that contains CNAME records for the requested zone and application, the ServerIron does not apply the GSLB policy to the CNAME records.

You can enable the ServerIron to search its GSLB database for the zone and application names in CNAME records. For example, if the ServerIron receives a DNS reply that contains the CNAME record shown above, and the zone and application name "www.foundrynet.com" have been configured on the ServerIron, the ServerIron will apply the GSLB policy to the CNAME record.

EXAMPLE:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# dns cname-detect

Syntax: [no] dns cname-detect

Possible values: N/A

Default value: disabled

Configures the GSLB ServerIron to remove all addresses except the best address from the DNS replies.

By default, the GSLB ServerIron retains the same number of IP addresses in the DNS replies from the DNS server. The GSLB policy swaps the IP address on the top of the list with the “best” address, selected by the GSLB policy. You can configure the ServerIron to remove all addresses except the one the GSLB policy selects as the best address.

EXAMPLE:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# dns best-only

Syntax: [no] dns best-only

To display the state of this feature, enter the show gslb policy command. The DNS best-only field indicates whether the feature is enabled or disabled.

Possible values: N/A

Default value: N/A

Specifies the value to which the GSLB ServerIron changes the TTL of each DNS record contained in DNS replies received from the DNS for which the ServerIron is a proxy.

EXAMPLE:

To change the TTL, enter commands such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# dns ttl 45

Syntax: [no] dns ttl <num>

The <num> parameter specifies the TTL and can be from 0 – 1000000000 seconds. The default is 10 seconds.

For all GSLB features except DNS cache proxy, the command no dns ttl configures the ServerIron to use the TTL from the DNS. If you are using DNS cache proxy, this command resets the TTL to 10.

Possible values: 0 – 1000000000 seconds

Default value: 10 seconds

Moves activity to the privileged EXEC level from any level of the CLI, with the exception of the user level.

EXAMPLE:

To move to the privileged level, enter the following from any level of the CLI.

ServerIron(config-gslb-policy)# end

ServerIron#

Syntax: end

Possible values: N/A

Default value: N/A

Moves activity up one level from the current level. In this case, activity will be moved to the global level.

EXAMPLE:

ServerIron(config-gslb-policy)# exit

ServerIron(config)#

Syntax: exit

Possible values: N/A

Default value: N/A

Disables or re-enables the FlashBack GSLB metric. This metric indicates how quickly the GSLB ServerIron receives Layer 4-7 health check results. This metric is enabled by default, which means the GSLB ServerIron uses this metric when evaluating the sites in a DNS reply to choose the best site.

EXAMPLE:

To disable this metric, enter the following command:

ServerIron(config-gslb-policy)# no flashback

To re-enable this metric, enter the following command:

ServerIron(config-gslb-policy)# flashback

Syntax: [no] flashback

Possible values: N/A

Default value: Enabled

Modifies the following FlashBack parameters:

• Application tolerance

• TCP tolerance

The GSLB ServerIron uses a tolerance value when comparing the FlashBack speeds of different sites. The tolerance value specifies the percentage by which the FlashBack speeds of the two sites must differ in order for the ServerIron to choose one over the other. The default FlashBack tolerance is 10%. Thus, if the FlashBack speeds of two sites are within 10% of one another, the ServerIron considers the sites to be equal. However, if the speeds differ by more than 10%, the ServerIron prefers the site with the lower FlashBack speed.

FlashBack speeds are measured at Layer 4 for all TCP/UDP ports. For the application ports known to the ServerIron, the FlashBack speed of the application is also measured.

When the ServerIron compares the FlashBack speeds, it compares the Layer 7 (application-level) FlashBack speeds first, if applicable. If the application has a Layer 7 health check and if the FlashBack speeds are not equal, the ServerIron is through comparing the FlashBack speeds. However, if only the Layer 4 health check applies to the application, or if further tie-breaking is needed, the ServerIron then compares the Layer 4 FlashBack speeds.

EXAMPLE:

To change the tolerances for the response times of TCP and application health checks, when used as a metric for selecting a site, enter commands such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# flashback application tolerance 30
ServerIron(config-gslb-policy)# flashback tcp tolerance 50

Syntax: [no] flashback application | tcp tolerance <num>

The application | tcp parameter specifies whether you are modifying the tolerance for the Layer 4 TCP health check or the Layer 7 application health checks. You can change one or both and the values do not need to be the same. For each, you can specify from 0 – 100. The default for each is 10.

Possible values: 0 – 100

Default value: 10

Disables or re-enables the geographic GSLB metric. This metric indicates the geographic location of a site. This metric is enabled by default, which means the GSLB ServerIron uses this metric when evaluating the sites in a DNS reply to choose the best site.

EXAMPLE:

To disable this metric, enter the following command:

ServerIron(config-gslb-policy)# no geographic

To re-enable this metric, enter the following command:

ServerIron(config-gslb-policy)# geographic

Syntax: [no] geographic

Possible values: N/A

Default value: Enabled

Adds a zone to the Weighted-ip metric.

EXAMPLE:

SLB-ServerIron(config-gslb-policy)# weighted-ip
SLB-ServerIron(config-gslb-policy)# gslb dns zone gslb.com

Syntax: [no] gslb dns zone <name>

Possible values: For <name>, enter up to 32 characters

Default value: N/A

Selects a sight for which to apply weights for the weighted site metric.

EXAMPLE:

The following commands enable the Weighted Site metric, selects the site SanJose, and configures a weight of 50 for the site.

SLB-ServerIron(config-gslb-policy)# weighted-site
SLB-ServerIron(config-gslb-policy)# gslb site SanJose
SLB-ServerIron(config-gslb-site-SanJose)# weight 50

Syntax: gslb site <site name>

Possible values: <site name> can have a maximum of 16 characters.

Default value: N/A

Disables or re-enables the health-check GSLB metric. This metric indicates whether the site has passed the Layer 4 and (if applicable) Layer 7 health checks. The GSLB ServerIron uses this metric when evaluating the sites in a DNS reply to choose the best site.

EXAMPLE:

To disable this metric, enter the following command:

ServerIron(config-gslb-policy)# no health-check

To re-enable this metric, enter the following command:

ServerIron(config-gslb-policy)# health-check

Syntax: [no] health-check

Possible values: N/A

Default value: Enabled

Globally configures the interval at which the distributed health check site ServerIrons report the health check information to the GSLB ServerIron. This applies if the GSLB ServerIron supports the distributed health check feature. Note that if health status interval is configured globally, it applies to all peer site ServerIrons that support the distributed health check feature.

EXAMPLE:

To globally configure the health status reporting interval, enter commands such as the following on the GSLB ServerIron:

GSLB-ServerIron(config)# gslb policy
GSLB-ServerIron(config-gslb-policy)# health-status-interval 3

Syntax: [no] health-status-interval <secs>

Possible values: 2 – 120 seconds

Default value: N/A

Enables or disables the WSM CPUs’ local least-response counter as the tiebreaker in the GSLB algorithm. By default, the GSLB policy has least-response as the tiebreaker in the GSLB algorithm. If round-robin has been configured as the tiebreaker, you must change it to least-response before you can configure least-response-local as the tiebreaker.

EXAMPLE:

ServerIron(config-gslb-policy)# least-response-local

Syntax: [no] least-response-local

Possible value: N/A

Default value: Disabled

Changes the order in which the GSLB ServerIron applies the policy metrics. To change the order, specify the metrics in the desired order.

EXAMPLE:

To specify a new GSLB policy order, enter a command such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# metric-order set health-check round-trip-time
capacity num-session flashback

This command changes the GSLB policy to the following:

• The health-check results

• The round-trip time between the remote ServerIron and the DNS client

• The site ServerIron’s session capacity threshold

• The site ServerIron’s available session capacity

• The site ServerIron’s FlashBack speed (how quickly the GSLB receives the health check results)

• The Least Response selection (the site ServerIron that has been selected less often than others)

Two of the metrics, server health and geographic location, are not specified. As a result, these metrics are not used when evaluating site IP addresses in the DNS responses.

To display the GSLB policy after you change it, enter the show gslb policy command. For more information, see the "Configuring Global Server Load Balancing" chapter in the Foundry ServerIron Installation and Configuration Guide.

Syntax: [no] metric-order set <list>

The <list> parameter is a list of the metrics you want to use, in the order you want the GSLB ServerIron to use them. The GSLB uses the metrics in the order you specify them. You can specify one or more of the following:

• active bindings – The VIP with the highest number of active bindings

• capacity – The site ServerIron’s available session capacity

• connection-load – The site ServerIron’s average number of new connections per second

• flashback – The site ServerIron’s FlashBack speed (how quickly the GSLB receives the health check results)

• geographic – The geographic location of the server

• health-check – The Layer 4 and application health checks

• num-session – The site ServerIron’s session capacity threshold

• preference – The administratively configured preference for the site ServerIron

• round-trip-time – The round-trip time between the remote ServerIron and the DNS client

• weighted-ip – The weight distribution of GLSB traffic among IP addresses in a DNS reply

• weighted-site – The weight distribution of SLB traffic among GSLB sites

There is no parameter for the Least Response Selection. This metric is always enabled and is always the last one in the policy.

To reset the order of the GSLB policy metrics to the default (and also re-enable all disabled metrics), enter the following command:

ServerIron(config-gslb-policy)# metric-order default

Syntax: metric-order default

The no metric-order set command also resets the order and re-enables all disabled metrics. This command is equivalent to metric-order default.

Possible values: any combination or order

Default value: The GSLB ServerIron applies the metrics in the following order:

• health-check

• weighted-ip

• weighted-site

• num-session

• active-bindings

• round-trip-time

• geographic

• capacity

• flashback

• administrative preference (when enabled; this metric is disabled by default)

• least-response (this metric is a tie-breaker and is always enabled and always last; you cannot disable or re-order this metric)

This command is used to disable other commands. To do so, place the word no before the command.

Disables or re-enables the GSLB metric for the site ServerIron’s session capacity threshold. The capacity threshold specifies how close to the maximum session capacity the site ServerIron (remote ServerIron) can be and still be eligible as the best site for the client. This mechanism provides a way to shift load away from a site before the site becomes congested. The GSLB ServerIron uses this metric when evaluating the sites in a DNS reply to choose the best site.

EXAMPLE:

To disable this metric, enter the following command:

ServerIron(config-gslb-policy)# no num-session

To re-enable this metric, enter the following command:

ServerIron(config-gslb-policy)# num-session

Syntax: [no] num-session

Possible values: N/A

Default value: Enabled

Specifies the percentage by which the number of available sessions on the site ServerIron can differ from the number of available sessions on another site ServerIron and still be considered an equally good site.

EXAMPLE:

To change the session-table tolerance metric, enter commands such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# num-session tolerance 20

Syntax: [no] num-session tolerance <num>

The <num> parameter specifies the maximum percentage by which the session table utilization on ServerIrons at different sites can differ without the GSLB ServerIron selecting one over the other based on this metric. You can specify a tolerance from 0 – 100. The default is 10.

Possible values: 0 – 100

Default value: 90

Enables the administrative preference GSLB metric.

To assign preference values for individual site ServerIron’s, see "si-name" .

EXAMPLE:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# preference

Possible values: N/A

Default value: Disabled

Enables the GSLB protocol on a site ServerIron.

For security, remote ServerIrons do not listen to TCP port 182 (the GSLB protocol port) by default. This means the GSLB protocol is disabled on remote site ServerIrons by default. For a remote ServerIron to use the protocol, you must enable the protocol on the remote ServerIron.

EXAMPLE:

To enable a remote ServerIron to use the GSLB protocol, enter the following command:

ServerIron(config)# gslb protocol

Syntax: [no] gslb protocol

Possible values: N/A

Default value: Disabled

This command returns you from any level of the CLI to the User EXEC mode.

EXAMPLE:

ServerIron(config-gslb-policy)# quit

ServerIron>

Syntax: quit

Possible values: N/A

Default value: N/A

The Round Robin Selection metric is an alternative to the Least Response Selection metric as the final tie breaker. When you enable Round Robin Selection, the GSLB ServerIron automatically disables the Least Response Selection metric, and instead uses the round-robin algorithm to select a site. Round Robin Selection chooses the first IP address in the DNS response for the first client request, then selects the next address for the next client request, and so on.

Use the Round Robin Selection metric instead of the Least Response Selection metric when you want to prevent the GSLB ServerIron from favoring new or recently recovered sites over previously configured active sites.

The Round Robin Selection metric is disabled by default. When you enable the metric, the software automatically disables the Least Response Selection metric, since they are mutually exclusive. Likewise, if you disable the Round Robin Selection metric, the software automatically re-enables the Least Response Selection metric.

To enable the Round Robin Selection metric, enter the following commands:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# round-robin

Syntax: [no] health-check | num-session | preference | round-robin | round-trip-time | geographic | capacity | flashback

When you enable this metric, the software automatically disables the Least Response Selection metric. if you disable the Round Robin Selection metric, the software automatically re-enables the Least Response Selection metric.

Possible values: N/A

Default value: Disabled

Disables or re-enables the GSLB metric for the round-trip time between the remote ServerIron and the DNS client. The Round-trip time (RTT) is the amount of time that passes between when the remote site initiates a TCP connection (sends a TCP SYN) to the client and when the remote site receives the client’s acknowledgment of the connection request (sends a TCP ACK). The GSLB ServerIron learns the RTT information from the site ServerIrons through the Foundry GSLB protocol and uses the information as a metric when comparing site IP addresses. The GSLB ServerIron uses this metric when evaluating the sites in a DNS reply to choose the best site.

EXAMPLE:

To disable this metric, enter the following command:

ServerIron(config-gslb-policy)# no round-trip-time

To re-enable this metric, enter the following command:

ServerIron(config-gslb-policy)# round-trip-time

Syntax: [no] round-trip-time

Possible values: N/A

Default value: Enabled

Changes the RTT cache interval, which specifies how often the site ServerIrons use the Foundry GSLB protocol to send RTT information to the GSLB ServerIron. The GSLB ServerIron stores this information in a cache. The GSLB ServerIron uses the entries in the cache when using the RTT metric to evaluate IP addresses in a DNS reply.

EXAMPLE:

To change the RTT cache interval, enter commands such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# round-trip-time cache-interval 30

The command in this example changes the RTT cache interval from 10 seconds to 30 seconds.

Syntax: [no] round-trip-time cache-interval <num>

The <num> parameter specifies the aging interval and can be from 10 – 300 seconds. The default is 10 seconds.

Possible values: 10 – 300 seconds

Default value: 10 seconds

Changes the RTT cache prefix, which specifies the level of aggregation that occurs in the GSLB ServerIron’s RTT cache. The entries in the RTT cache include IP address information for the clients. To avoid overflowing the cache, cache entries are aggregated based on the IP information. For example, if the GSLB ServerIron receives RTT information for clients at 192.21.4.69 and 192.21.4.18, and the cache prefix is 31 bits, both addresses go in as separate entries. However, if the prefix is 16 bits, the GSLB ServerIron aggregates the addresses. In this case, only one entry, 192.21.x.x goes in the cache.

EXAMPLE:

To change the RTT cache prefix, enter commands such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# round-trip-time cache-prefix 16

The command in this example changes the RTT cache prefix from 20 bits to 16 bits.

Syntax: [no] round-trip-time cache-prefix <num>

The <num> parameter specifies the number of significant bits in the prefix and can be from 1 – 31. The default is 20.

Possible values: 1 – 31

Default value: 20

Changes the RTT explore percentage, which prevents the GSLB ServerIron from unfairly biasing selection of the best site based on previous RTT responses.

Site ServerIrons send RTT information only for the sessions that clients open with them. These are clients referred to the site ServerIron by the GSLB ServerIron. If the metrics that come before this one (based on the GSLB policy order) do not select a “best” site, the ServerIron selects a site based on RTT.

Since the only RTT information received by the GSLB ServerIron comes from the site ServerIrons to which the GSLB ServerIron has referred clients, it is possible for the GSLB ServerIron to continually bias its selection toward the first site ServerIron that sent RTT information. To prevent this from occurring, the GSLB ServerIron intentionally ignores the RTT metric for a specified percentage of the requests from a given client network. You can specify an RTT explore percentage from 0 – 100. The default is 5. By default, the GSLB ServerIron ignores the RTT for 5% of the client requests from a given network.

EXAMPLE:

To change the RTT explore percentage, enter commands such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# round-trip-time explore-percentage 10

The command in this example changes the RTT explore percentage from 5% to 10%.

Syntax: [no] round-trip-time explore-percentage <num>

The <num> parameter specifies the explore percentage and can be from 0 – 100. The default is 5.

Possible values: 0 – 100

Default value: 5

Changes the RTT tolerance. When the GSLB ServerIron compares two site IP addresses based on RTT, the GSLB ServerIron favors one site over the other only if the difference between the RTT values is greater than the specified percentage. This percentage is the RTT tolerance. You can set the RTT tolerance to a value from
0 – 100. The default is 10%.

EXAMPLE:

To change the RTT tolerance, enter commands such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# round-trip-time tolerance 70

The command in this example changes the RTT tolerance from 10% to 70%.

Syntax: [no] round-trip-time tolerance <num>

The <num> parameter specifies the percentage above which the RTTs of two sites must differ for the GSLB ServerIron to favor one site over the other based on the RTT. You can specify a value from 0 – 100. The default is 10%.

Possible values: 0 – 100%

Default value: 10%

Displays the real and virtual server configuration information on a remote site ServerIron in the GSLB ServerIron’s CLI. The command also displays the session and CPU information used by the GSLB policy. You can view detailed configuration information and statistics for the site ServerIron, from the GSLB ServerIron’s management console. For more information, see the "Configuring Global Server Load Balancing" chapter in the Foundry ServerIron Installation and Configuration Guide.

Displays a variety of configuration and statistical information about the ServerIron. To see a description of the show commands, see "Show Commands" .

Adds static prefix information to the cache. For example, you can add static cache entries with longer prefix information than the dynamic cache entries to ensure that RTT information is stored under the static entries instead of dynamic cache entries with shorter prefixes. This is useful when you want to ensure that certain prefixes are always present in the cache regardless of how often the GSLB ServerIron receives RTT data for them. Static prefixes do not age out.

EXAMPLE:

To add a static prefix cache entry, enter commands such as the following:

ServerIron(config)# gslb policy
ServerIron(config-gslb-policy)# static-prefix 61.1.1.1/20

Syntax: static-prefix <ip-addr>/<prefix-length>

The <ip-addr> specifies the address of the cache entry. This is not necessarily the address of a remote site. The address you specify here is combined with the prefix length to result in a network prefix (network portion of an IP address). The prefix length can be from 1 – 31.

You can enter more than one prefix on the same command line. Separate each prefix with a space. You can configure up to 250 static prefixes on a ServerIron.

The command in this example configures an entry for address 61.1.1.1 with a prefix of 20 bits. (Due to the prefix length, the value actually stored in the cache is 61.1.0.0.20.) When the GSLB ServerIron receives RTT information for an address within the specified prefix, the GSLB ServerIron stores the information in the static prefix entry configured above, instead of creating a dynamic entry.

Possible values: See above.

Default value: N/A

Disables or re-enables the Weighted IP metric. This metric provides a way for the ServerIron to distribute GSLB traffic among IP addresses in a DNS reply, based on weights assigned to the IP addresses.

EXAMPLE:

To enable this metric, enter the following command:

SLB-ServerIron(config-gslb-policy)# weighted-ip

Syntax: [no] weighted-ip

Possible values: N/A

Default value: Disabled

Disables or re-enables the Weighted-Site metric. This metric provides a way for the ServerIron to distribute SLB traffic among GSLB sites based on weights configured for the sites.

EXAMPLE:

To enable the Weighted Site metrics, enter the following command:

SLB-ServerIron(config-gslb-policy)# weighted-site

Syntax: [no] weighted-site

Possible values: N/A

Default value: Disabled

Saves the running-time configuration into the startup-config file.

EXAMPLE:

ServerIron(config-gslb-policy)# write memory

Syntax: write memory

Possible values: N/A

Default value: N/A

Displays the running-configuration of the ServerIron on the terminal screen.

EXAMPLE:

ServerIron(config-gslb-policy)# write terminal

Syntax: write terminal

Possible values: N/A

Default value: N/A