Need help with Routers Configuration (Static Routing)

Hi Folks,

I am fairly new to the Cisco world and this is my first post on this forum.

Background:

I have a couple of 3600 routers that are connected back-to-back. I am having problems configuring static routing on the routers.

Once I am done configuring the IP addresses and the routes, the "sh ip route" command does not display anything.

A couple of things look funny are as follows:

a, I can't seem to bring the "line protocol" up on the interfaces.
b, One of the routers keeps displaying the following message intermitantely

02:15:27: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to down
02:15:37: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to up

The running configs for the two routers are as follows

Bottom Router Configuration:

Bottom#sh run
Building configuration...

....
!
ip subnet-zero
!
....
!
interface Ethernet2/0
description Ethernet Interface (e2/0)
ip address 200.100.50.1 255.255.255.0
half-duplex
!

interface Serial2/0
description Network connection to Top network
ip address 10.1.1.1 255.0.0.0
clock rate 64000
!

interface TokenRing2/0
no ip address
shutdown
ring-speed 16
!
ip classless

Top Router Configuration

sh
02:15:07: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to up run
Building configuration...

....

!

interface Ethernet0/0
description Ethernet Interface (e0/0)
ip address 192.168.10.1 255.255.255.0
half-duplex
!
interface Serial0/0
description Network connection to Bottom network
ip address 10.1.1.2 255.0.0.0
!
interface BRI0/0
no ip address
encapsulation hdlc
shutdown
!
ip classless
ip route 0.0.0.0 0.0.0.0 Serial0/0
ip route 200.100.50.0 255.255.255.0 10.1.1.1
no ip http server
!

Can somebody please point out an obvious mistake ?

Thanks in advance.

rogers42

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Comments

bighornsheep

Make sure your bottom router has the DCE cable since that's where you've specify a clockrate. Try to do a shutdown and then a no shut shortly after on the two serial interfaces.

Netstudent

I concur....Do a show controllers serial 2/0 to see if it is DCE or DTE.

r_durant

Yup...ditto on the two responses

You may just have the ends turned around...

rogers42

Hi Folks,

Thanks for the quick & multiple replies

Following is what I have tried thus far

Checked the DTE/DCE ends and all seem to be in order.
Manually closed (shutdown) and opened (no shut) the ethernet & serial interfaces on both routers. Serial interfaces are up on both routers.
I can see the routing table on both routers.
I can even ping both serial interfaces (from the far router)

Here is the problem

The "line protocol" state is "down" for ethernet interfaces on both routers
I cannot ping the ethernet interfaces.

Q, I realize that for serial interfaces, the MTU size and the encapsulation types should match in order for the "line protocol" state to be "UP". How about the ethernet ports ? Any ideas as to the configurations ?

Thanks in advance.

rogers42

mikej412

rogers42 wrote:

The "line protocol" state is "down" for ethernet interfaces on both routers
I cannot ping the ethernet interfaces.

What are they plugged into? What kind of cables?

If you're not plugged into anything -- you can just use Loopback interfaces to get "additional networks" to practice routing..... or you can issue the no keepalive command on the ethernet interfaces.

rogers42

Hi,

I think thats it !!! Nothing is plugged into the ethernet ports. I will try both options as suggested.

Thanks

rogers42

rogers42

Thanks for the suggestions. I tried both the suggestions (i.e. turning the keepalive timer OFF as well as creating loopbacks) and both worked.

Can somebody please shed some light on the theory behind both options ? (i.e. why do they work)

rogers42