Timers spf – LevelOne GTL-2690 User Manual

Page 735

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IP Routing Commands

42-22

42

System Boundary Router (ASBR). However, an ASBR does not, by default,
generate a default route into the routing domain.
- If you use the always keyword, the router will advertise itself as a default

external route into the AS, even if a default external route does not actually
exist. (To define a default route, use the ip route command.)

- If you do not use the always keyword, the router can only advertise a

default external route into the AS if the redistribute command is used to
import external routes via RIP or static routing, and such a route is known.

• Type 1 route advertisements add the internal cost to the external route metric.

Type 2 routes do not add the internal cost metric. When comparing Type 2
routes, the internal cost is only used as a tie-breaker if several Type 2 routes
have the same cost.

Example
This example assigns a metric of 20 to the default external route advertised into an
autonomous system, sending it as a Type 2 external metric.

Related Commands

ip route (42-2)
redistribute (42-25)

timers spf

This command configures the hold time between making two consecutive shortest
path first (SPF) calculations. Use the no form to restore the default value.

Syntax

timers spf spf-holdtime
no timers spf

spf-holdtime - Minimum time between two consecutive SPF calculations.
(Range: 0-65535 seconds)

Command Mode

Router Configuration

Default Setting

10 seconds

Command Usage

• Setting the SPF holdtime to 0 means that there is no delay between

consecutive calculations.

• Using a low value allows the router to switch to a new path faster, but uses

more CPU processing time.

Console(config-router)#default-information originate metric 20
metric-type 2
Console(config-router)#

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