RIPv1 Advertising Question

One question had me pretty confused. It was asking how to specify some networks through RIP v1.

There were a few options on how to advertise the two addresses. They were something like:
10.33.0.1
10.65.0.1

A.
router rip
network 10.0.0.0

B.
router rip
network 10.33.0.0
network 10.65.0.0

C.
router rip
network 10.33.0.1 255.0.0.0
network 10.65.0.1 255.0.0.0

Right when I read the question I was like "oh, ok, I'll just select 10.0.0.0 because we all know that RIP is classful". But then I read further, and it wanted me to SELECT 2.

I can't remember all of the options. But what other options ARE THERE other than just 'network 10.0.0.0' for advertising 2 Class A addresses?

Find more posts tagged with

Save $250 on 2025 certification boot camps from Infosec!

Book now with code EOY2025

Button

Comments

Danman32

You can use B. It's a bit redundant I agree, but it will work, and may be clearer to someone reading the config.

mzinz

What a retarded question.

I knew that, and its so simple, but the question started making me think that you could advertise the two as seperate networks or something. I wasn't even thinking redundant.. all that came to my head was "Why would someone advertise both of them"

mp3spy

Yea I think b too. RIP does not advertise the MASK either.....So B would fall into that category..

david_r

2501R2(config)#router rip
2501R2(config-router)#network 10.0.0.0
2501R2(config-router)#
RIP: sending general request on Loopback2 to 255.255.255.255
RIP: sending general request on Loopback3 to 255.255.255.255
RIP: sending v1 update to 255.255.255.255 via Loopback2 (10.33.0.1)
     subnet  10.65.0.0, metric 1
RIP: Update contains 1 routes
RIP: Update queued
RIP: Update sent via Loopback2
RIP: sending v1 update to 255.255.255.255 via Loopback3 (10.65.0.1)
     subnet  10.33.0.0, metric 1
RIP: Update contains 1 routes
RIP: Update queued
RIP: Update sent via Loopback3

EdTheLad

The only correct answer here is A, Rip is advertised by using the "network"command followed by the classful major network.
In your case all examples include a 10.x.x.x major network so all interfaces that have 10 in the first octet will enable rip and advertise all 10.x.x.x subnets, except the local interface subnet.

david_r

ed, Danman,
Can you explain that again? If I enter the following code,

2501R2(config)#router rip
2501R2(config-router)#no network 10.0.0.0
2501R2(config-router)#network 10.33.0.0
2501R2(config-router)#network 10.65.0.0

My config will be:

router rip
 network 10.0.0.0

EdTheLad

A value of 10 in the first octet indicates a class A network, therefore the classful network address for a class A network is the number in the first octet followed by 0's in the last 3 octets.
Rip,Ripv2 and IGRP are classified using the classful network address.So if you have afew interfaces with 10.x.x.x addresses you just have to specify the 10.0.0.0 classful address.If there are some interfaces you dont want the routing protocol enabled on you can use the "passive-interface" command, but these interfaces will still have their ip addresses included in the updates.

zero-g-smith

I think Ed_the_lad meant the correct answer was A. Not B.
Correct me if Im wrong.

EdTheLad

zero-g-smith wrote:

I think Ed_the_lad meant the correct answer was A. Not B.
Correct me if Im wrong.

Yep, i didnt see that

, i'll do a quick edit!