CISCO IOS in a Nutshell

Name

timers basic — router

Synopsis

timers basic update-value 
               invalid-value 
               holddown-value 
               flush-value [sleeptime-value]
no timers basic

Configures

Routing protocol timers

Default

The default timer values are shown in Table 15-21

Table 17-8. Default timer values

Timer	IGRP	RIP default
Update	90 seconds	30 seconds
Invalid	270 seconds	180 seconds
Holddown	280 seconds	180 seconds
Flush	630 seconds	240 seconds
Sleeptime	0 milliseconds	N/A

Description

This command allows you to adjust the routing timers. All values expect for sleeptime are in seconds.

update-value

The interval at which routing updates are sent.

invalid-value

The interval after which a route is considered invalid if an update does not arrive.

holddown-value

The time that the router waits after deciding that a route is invalid before accepting further information about it. For example, if a router decides that a certain route has become invalid, it waits for the hold-down period to pass before believing any other information stating that the route is valid. This procedure helps to maintain routing stability.

flush-value

The interval after which invalid routes are purged from the routing table.

sleeptime-value

Optional. This timer’s value is the interval in milliseconds to wait after a flash update. This value should be less than the update value. Sleeptime is not applicable to RIP.