On-Demand Routing Commands

This chapter explains the function and syntax of the On-Demand Routing (ODR) commands. For more information about defaults and usage guidelines, see the corresponding chapter of the Cisco IOS IP and IP Routing Command Reference, Release 12.1.

router odr

To configure a router to accept On-Demand Routing (ODR) routes from a stub routers, use the router odr global configuration command. To disable ODR, use the no form of this command.

router odr process-id

no router odr process-id

Syntax Description

process-id

Number of a process that identifies the routes to the other ODR routers.

process-id	Number of a process that identifies the routes to the other ODR routers.

timers basic (ODR)

To adjust ODR network timers, use the timers basic router configuration command. To restore the default timers, use the no form of this command.

timers basic update invalid holddown flush [sleeptime]

no timers basic

Syntax Description

update

Rate in seconds at which updates are sent. This is the fundamental timing parameter of the routing protocol.

invalid

Interval of time in seconds after which a route is declared invalid; it should be at least three times the value of the update argument. A route becomes invalid when there is an absence of updates that refresh the route. The route then enters holddown. The route is marked inaccessible and advertised as unreachable. However, the route is still used for forwarding packets.

holddown

Interval in seconds during which routing information regarding better paths is suppressed. It should be at least three times the value of the update argument. A route enters into a holddown state when an update packet is received that indicates the route is unreachable. The route is marked inaccessible and advertised as unreachable. However, the route is still used for forwarding packets. When holddown expires, routes advertised by other sources are accepted and the route is no longer inaccessible.

flush

Amount of time in seconds that must pass before the route is removed from the routing table; the interval specified must be at least the sum of the invalid and holddown arguments. If it is less than this sum, the proper holddown interval cannot elapse, which results in a new route being accepted before the holddown interval expires.

sleeptime

(Optional) Interval in milliseconds for postponing routing updates in the event of a flash update. The the sleeptime value should be less than the update time. If the sleeptime is greater than the update time, routing tables will become unsynchronized.

update	Rate in seconds at which updates are sent. This is the fundamental timing parameter of the routing protocol.
invalid	Interval of time in seconds after which a route is declared invalid; it should be at least three times the value of the update argument. A route becomes invalid when there is an absence of updates that refresh the route. The route then enters holddown. The route is marked inaccessible and advertised as unreachable. However, the route is still used for forwarding packets.
holddown	Interval in seconds during which routing information regarding better paths is suppressed. It should be at least three times the value of the update argument. A route enters into a holddown state when an update packet is received that indicates the route is unreachable. The route is marked inaccessible and advertised as unreachable. However, the route is still used for forwarding packets. When holddown expires, routes advertised by other sources are accepted and the route is no longer inaccessible.
flush	Amount of time in seconds that must pass before the route is removed from the routing table; the interval specified must be at least the sum of the invalid and holddown arguments. If it is less than this sum, the proper holddown interval cannot elapse, which results in a new route being accepted before the holddown interval expires.
sleeptime	(Optional) Interval in milliseconds for postponing routing updates in the event of a flash update. The the sleeptime value should be less than the update time. If the sleeptime is greater than the update time, routing tables will become unsynchronized.

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