Frame Relay and Ip unnumbered

[rkmorrow]

Is there any problem with breaking a point to point T1 line, that is using Ip Unumbered on the serial interface, and configuring it for multipoint into a frame relay cloud?
If all other configurations are correct, can't I use the ethernet ip address for the serial interface also?
If anyone can answer this I would appreciate it.
Thanks,
rkmorrow

 

[wybnormal]

I normally do not recommend using unnumbered interfaces unless you are absolutely out of IPs. It will work but you give up the telnet access to the port. So you need to make sure you have some other way of getting into the port.

To further add to this is the following technical paper from Cisco which suggests that unnumbered is really only for point to point due to how the router handles the next hop for routing.

http://www.cisco.com/warp/public/701/20.html

Mike S


"Diplomacy; the art of saying 'nice doggie' till you can find a rock" Wynn Catlin

 

[rkmorrow]

Wybnormal,
Thank you for your response, I have seen your posts here and you are experienced and want to help everyone if you can. That is decent.
If you have seen my posts, you have probably laughed, because I am very new to router configuation and am driving everyone nuts with my stupid questions.
Having said that, I have another maybe obvious question:
Why, when I see a configuration of an ethernet and serial port on the same router,(not always, but sometimes)I will see:
Ethernet0 10.66.34.10 255.255.255.0
Serial0 10.65.1.1 255.255.255.0
Now, my understanding is that the interfaces(serial AND ethernet)have to be on the same SUBNET for them to see each other.
Is this true, and how could the above example work when they are clearly on the different networks according to their masks.
If you know of where I can find any information that could help I would appreciate it.
Thanks,
rkmorrow

 

[wybnormal]

THanks for the kind words

To answer your 2nd question, can we spell "router"? ...what happens is the router will automaticly route between directly connection interfaces no matter what the subnet is on either interface. You can turn this off if want to make the router into a bridge but that is pretty self defeating.

For example, I have on a test set the following interfaces..

E0 is 192.168.50.1 and the S0 is 172.24.19.1

Two subnets right? but the router sees BOTH as directly connected if you do a SHOW IP ROUTE command. It *knows* to route between the two interfaces.

Mike S
"Diplomacy; the art of saying 'nice doggie' till you can find a rock" Wynn Catlin

 

[mbhandari]

Hi RK,
For router few tips.
1. Each interface have to be on different subnet.
2. Router sharing the link with each other should be on same subnet.

net1---RTR--net2----RTR-------net3

-bhandari