help Regarding RIP?

[imran_mcse]

As we know that RIP defend routing loops with the help of hold down timers.

Let's assume there are 5 routers connected like a ring (serial connections). and the serial link between two routers failed and some routers has learned a network from that side with metric 2 but now link is fail the can access same network with metric 4. so kindly tell me that RIP will wait for 180 sec. to make the metric 4 in routing table or it will immediately add this connected 4 metric route.I am asuming that there is no any loop chances.

Pls reply soon.

[olufemi.amao]

The timer only stops if it receives a message from the neighboring router that initially informed the network of the downed link .

so in your case it will wait for the hold timer to lapse.

[ankurbhasin]

Routing table is not immdeiately updated. Once the link goes down it will wait for the hold down period to expire (depends what is the hold down timer that time but less then 180 sec by default) and once the hold down timer is expired it will flush the old entry after flush timer and expires and update the new routing entry so no chances of routing loop as other features in RIP also protect routing loop like slit horizon and poision reverse.

HTH

Ankur

[amit-singh]

Hi,

Just to add on to Ankur's reply, it will wait holddowntime + 30 sec(default update period) more to update its routing table.

regards,

-amit singh