Modify Spf Timers; Modify Redistribution Metric Type; Modify Administrative Distance - Foundry Networks FESX Manual

Foundry Configuration Guide for the FESX, FSX, and FWSX
The metric-type <type> parameter specifies the external link type associated with the default route advertised
into the OSPF routing domain. The <type> can be one of the following:
• 1 – Type 1 external route
• 2 – Type 2 external route
If you do not use this option, the default redistribution metric type is used for the route type.
NOTE: If you specify a metric and metric type, the values you specify are used even if you do not use the always
option.

Modify SPF Timers

The Layer 3 Switch uses the following timers when calculating the shortest path for OSPF routes:
• SPF delay – When the Layer 3 Switch receives a topology change, the software waits before it starts a
Shortest Path First (SPF) calculation. By default, the software waits five seconds. You can configure the SPF
delay to a value from 0 – 65535 seconds. If you set the SPF delay to 0 seconds, the software immediately
begins the SPF calculation after receiving a topology change.
• SPF hold time – The Layer 3 Switch waits for a specific amount of time between consecutive SPF
calculations. By default, the Layer 3 Switch waits ten seconds. You can configure the SPF hold time to a
value from 0 – 65535 seconds. If you set the SPF hold time to 0 seconds, the software does not wait between
consecutive SPF calculations.
You can set the delay and hold time to lower values to cause the Layer 3 Switch to change to alternate paths more
quickly in the event of a route failure. Note that lower values require more CPU processing time.
You can change one or both of the timers. To do so, enter commands such as the following:
FESX424 Router(config-ospf-router)# timers spf 10 20
The command in this example changes the SPF delay to 10 seconds and changes the SPF hold time to 20
seconds.
Syntax: timers spf <delay> <hold-time>
The <delay> parameter specifies the SPF delay.
The <hold-time> parameter specifies the SPF hold time.
To set the timers back to their default values, enter a command such as the following:
FESX424 Router(config-ospf-router)# no timers spf 10 20

Modify Redistribution Metric Type

The redistribution metric type is used by default for all routes imported into OSPF unless you specify different
metrics for individual routes using redistribution filters. Type 2 specifies a big metric (three bytes). Type 1
specifies a small metric (two bytes). The default value is type 2.
To modify the default value to type 1, enter the following command:
FESX424 Router(config-ospf-router)# metric-type type1
Syntax: metric-type type1 | type2
The default is type2.

Modify Administrative Distance

Foundry Layer 3 Switches can learn about networks from various protocols, including Border Gateway Protocol
version 4 (BGP4), RIP, and OSPF. Consequently, the routes to a network may differ depending on the protocol
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