Routing & Lab Scenario Question

[Vrupani]

Hello

I am new to routers as such need some clarification on key concepts and a lab related setup question. I currently have a cisco 2501 and 2522 router connected via a back to back cable through ser0. The following are my questions. Any help would be greatly appreciated.

1. What is the specific command to set a clock rate on the Dce device, to prevent to from going down and up? Currently I have to disable keepalive on both the ser interfaces.

2. Do both the routers seria0 interfaces need to be in the same network,example: same network id/mask. Can routing protocols discover other routers not within the same network? Currently I have the following ip scheme.

2501 e0 169.254.24.254 255.255.255.0
s0 10.10.10.1/24

2522 e0 100.100.100.254 255.255.255.0
s0 101.10.10.25/24

The s0 interfaces are connected directly to each other via a back to back cable.
A show ip route on each router, displays the local e0 and s0 ip addresses and status as connected.

3. What else needs to be done to the ser0 interfaces once they are connected via the back to back cable? I cannot ping the other interfaces from each router. I can ping the interfaces locally on each router. I am assuming I need to enable a routing protocol or change the network id or both. Please let me know the specific steps involved.

Thanks
Vishal

 

[Guest_imported]

There are a few ways to configure your S0 interfaces. First use the clockrate command to set your clock and the bandwidth command to set bandwidth.

Each end of your serial connections must be in the same subnet. Usually to conserve addresses, either ip unnumbered or /30 is your best bet. Using a /24 will chew up way too many addresses. Once you get these in the same subnet, they should work fine.

 

[hexn]

Just set the clockrate on the router that has the DCE side of the serial cable. If you attempt to set the clockrate on the wrong side, the router will give you an error and reject the config change.

This should allow you to ping across.

config t
int s0
clockrate 130000

130000 is about T1 speed. ~~~~~~~~~~

http://shnypr.com

tech@shnypr.com
~~~~~~~~~~

 

[tango2002]

Well, if you are using frame-relay it will
gives you some problems with DCE and keepalives.
But if using x25, encap ppp, hdlc, it will be fine.
a. set ip on both routers to be same subnet.
b. set clockrate and dce, on dce side
c. set ip address - same subnet

It should works fine. I was preparing for CCNP
and run into same problem.
Hope it helps...

 

[okanyilmaz]

1.in global configuration mode

clock rate 56000

2.both ends must be in the same subnet

such as

160.75.73.1
160.75.73.2

3.
u can activate rip in order to gain access from one router to anothers neighbors.

in global conf mode type;

router rip

version 2

network A.B.C.D (this network is the router's neighbor)

after configuring the interface remember to type no shutdown to make your commands work.