A question about default route in RIP

[teru-lei]

Hi All,

I run RIP in the following enviroment:

e2/2--R1----R2---

I config RIP in the interfaces between R1 and R2. An I config command " ip route 0.0.0.0 0.0.0.0 e2/2" in R1. when I use "show ip rip data" in R1, I can see the 0.0.0.0 route in the RIP database as " redistributed" but I can not see the default route in R2, also I use " debug ip rip " in R2 but also can not see the 0.0.0.0 route contain in update. I tried to add command " default-information originate" in R1 but still the same. Does anybody know the reason? Thank You!

Best Regards

Teru Lei

[ruwhite]

Are you configuring redistribution? Try configuring a default metric.

Russ

[thisisshanky]

Well there is no need for a default metric, because RIP automatically redistributes default static routes with a metric of 1. I think you need to check to see if the ethernet interface is up or not. I tested this in lab, and i am getting the route redistributed.

r1#sh ip route

Gateway of last resort is 0.0.0.0 to network 0.0.0.0

20.0.0.0/24 is subnetted, 1 subnets

C 20.1.1.0 is directly connected, Serial0

10.0.0.0/24 is subnetted, 1 subnets

C 10.1.1.0 is directly connected, Ethernet0

S* 0.0.0.0/0 is directly connected, Ethernet0

r1#

r2#sh ip route

Gateway of last resort is 20.1.1.1 to network 0.0.0.0

20.0.0.0/24 is subnetted, 1 subnets

C 20.1.1.0 is directly connected, Serial0

R* 0.0.0.0/0 [120/1] via 20.1.1.1, 00:00:06, Serial0

HTH

[teru-lei]

Hi ruwhite,

Thanks for your reply, but the ethernet interface is up. Because if the interface is down, the default route will not be shown in the routing table and the rip datebase also will not show the default route or show "is possibly down". Do you think there is any other issue? or I had made any mistake?I also think the default route will be distributed to other rip routers...

Best Regards

Teru Lei

[thisisshanky]

Can you provide the configs of both r1 and r2. Also if possible, get the output of "sh ip route", for further troubleshooting.

[ruwhite]

Not necessarily. :-) When the RIP database code went in, the default redistribution of the default route was pulled out. That should be in 12.2 someplace, but I don't remember specifically where. So, it's going to depend on the version you're running--to be safe, redistribute static, and put a default metric in.

Russ

[thisisshanky]

Russ,

that was a nice tip!

[teru-lei]

Hi All,

Thanks for your reply. I am running IOS 12.1. My concern is : why I can see the route in the RIP database but the router did not advertise it ( I used "debug ip rip"in R2 but can not see the update contain the route 0.0.0.0, but others can!). I also tried: "default-metic 2" in R1. "default-information originate"in R1, also the same. However, when I change the default route to "ip route 0.0.0.0 0.0.0.0 x.x.x.x " (x.x.x.x is the ip that e2/2 is connected), although the rip database can not see the route, when I use "default-information originate" in R1 I can see the route in R2 and also the rip database in R1. I am looking for another router to try again. If any one has opinion, please just post here. Thank You!

Best Regards

Teru Lei