Routing question

Talic · November 2008

Maybe explaining my situation would be best:
I have about 6 WAN serial links set up with a address of 192.168.1.XX/30 and the routing protocols found the various network WAN links fine. I have 5 routers hooked into those interfaces and each router hooked into a LAN with computer behind it. When I configured the LAN networks I used a address 192.168.N.XX/24. Wheres the N is the LAN different networks from 2 to 6

My question is, do I need to type in each different LAN network number to get the routing protocols to up date their routing table with the LAN networks? I did get RIP2 working on the WAN links but I'm not sure how to input the LAN behind each router.

kalebksp · November 2008

I'm not sure I exactly understand how you have your network setup, but for RIP you have to do a "network 192.168.X.0" for each network you want to advertise and each network you want to send out advertisements on

-Kale.

Talic · November 2008

I typed in network 192.168.0.0 and I was going to let RIP find the subnets.

Todd used a example that if you had subnets of 172.16.10.0 and 172.16.20.0 along with 172.16.30.0 with the classful subnet mask of /24, you could just type in network 172.16.0.0 and it'll work. Shouldn't 192.168.0.0 work with class c address or would you need to specify the 3rd octet?

I would think it wouldn't do any classful stuff with rip2 and eigrp but it seems like it wants to do the classful crap.

Gotta change all my ip address to 10.0.0.0 or 172.16.0.0 I guess

kalebksp · November 2008

It looks like you have to enter the classful address of the network, if that network were subnetted it would find all the networks under it. When you entered 192.168.0.0 it was trying to add the network 192.168.0.0/24. So, as you said, you would have to move them to a class A or B network (or subnet the class C you were using).

-Kale

jason_lunde · November 2008

172.16.x.x is a class B address, so in a classful network, even if you are using it with a class c mask (255.255.255.0 or /24), simply typing 172.16.0.0 into your RIP config will work. However, with a classful class c address such as 192.168.1.x, you will have to type in each one (ie 192.168.2.x....3.x.....4.x. Which version of RIP are you using?

Talic · November 2008

jason_lunde wrote:

172.16.x.x is a class B address, so in a classful network, even if you are using it with a class c mask (255.255.255.0 or /24), simply typing 172.16.0.0 into your RIP config will work. However, with a classful class c address such as 192.168.1.x, you will have to type in each one (ie 192.168.2.x....3.x.....4.x. Which version of RIP are you using?

Yeah, it clicked after I tried doing it, hehe. I was thinking about the range of network addresses reserved for private use, which were 192.168.1.0 up to 192.168.255.0 I believe.

I redid the addresses using RIP 2 and the private 10.0.0.0 address block with 10.1.1.0 block used for WAN connections and 10.1.X.0 used for the LAN with a computer behind it. I did under router config: network 10.0.0.0 and rip doesn't seem to be advertising the LAN networks behind the routers but isn't supposed to find them? I added them statically two days ago and it worked but with using rip it doesn't seem to. All the LAN's networks are showing up on show ip route.

The static routes are gone now since I've been using rip.

Talic · November 2008

I don't want to make another thread but I wanted to ask another quick question: I looked at the objectives for CCENT and it only says to configure RIP on it, would it bee a good idea to hold off on EIGRP and OSPF for ICND2? EIGRP and OSPF are a lot to chew on right now.

Netwurk · November 2008

RIP v2 should do what you want if you turn off autosummary. The command is "no auto-summary"

phantasm · November 2008

Talic wrote:

I don't want to make another thread but I wanted to ask another quick question: I looked at the objectives for CCENT and it only says to configure RIP on it, would it bee a good idea to hold off on EIGRP and OSPF for ICND2? EIGRP and OSPF are a lot to chew on right now.

Yes. The info on Cisco's site says that OSPF and EIGRP are on the ICND2 exam. No need to sweat it for the ICND1.

bighornsheep · November 2008

Even if you're using RIPv2 with no auto-summary command,

network 10.10.1.0

for example will still turn into

network 10.0.0.0

when you do a show run.

RIP in its nature is a classful protocol, V2 simply uses the previously unused bits in the message to pass the subnet mask information.

Netwurk · November 2008

The "no auto-summary" should work for him.

Here's a config straight from a ciscopress book:

!
interface Ethernet0
ip address 128.200.1.1 255.255.255.0
!
interface Ethernet1
ip address 128.200.2.1 255.255.255.0
!
router rip
version 2
network 128.200.0.0
no auto-summary

If you had auto-summary on, RIP would see both interfaces as being in the same network.

Talic · November 2008

Cool, thanks guys

Talic · November 2008

Another question, when modifying RIP do you need to enter version 2 every time? Is just turning on RIP 2 once enough?

Maybe I should of named this thread "Talic's question thread"

Netwurk · November 2008

Talic wrote:

Another question, when modifying RIP do you need to enter version 2 every time? Is just turning on RIP 2 once enough?

Maybe I should of named this thread "Talic's question thread"

Once you set RIP as version 2, it should stay that way unless you do a "no router rip" and start over.

Do a show run command and look at the RIP config if you're not sure which version you set.

Routing question

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