Point to point Framerelay link not working.

[ashishpanda]

Hi

I am testing a simple scenario in the LAB. Two routers connected back to back with V.35 serial cables.Routers pinging end to end when serial encapsulation is HDLC or PPP.The line protocol is not coming UP when Encapsulation used on the serial is Frameraelay. The related configuration is as follows.

R1

Int s0

encapsulation frame-relay

R2

int s0

clock rate 128000

encapsulation frame-relay

Any idea why this is happening? Am i missing any thing?

Thanks and regards

Ashish

[desai.jaideep]

Hi

Just mentioning encap as frame-relay won't do.There are few more settings for it.

Pls refer to following for more help

http://www.cisco.com/warp/public/125/12.html

You will bascically need 3 routers.Two as clients and one as Frame-relay Switch.

The config for frame-relay switch will be

int s0

encap frame-relay

frame-relay intf-type dce

frame-relay route 101 Serial1 102

clock rate 64000

!

int S1

encap frame-relay

frame-relay intf-type dce

frame-relay route 102 Serial0 101

clock rate 64000

interface S0

ip address x.x.x.x x.x.x.x

encapsulation frame-relay

frame-relay interface-dlci 101

interface S0

ip address x.x.x.x x.x.x.x

encapsulation frame-relay

frame-rel interface-dlci 102

(Pls check for spelling mistakes)

Pls revert back if u have any prob.

Regards

JD

[Richard Burts]

JD is right that the best way to do it is to have 3 routers where one of the routers functions as a frame relay switch. I have set it up in the lab with routers back to back and with encapsulation frame-relay (without the third router) so I know it can be done. But it does need to accomodate the need for LMI in Frame Relay and it is a lot more complex that just setting the encapsulation on the interface.

Looking at it from another perspective, both PPP and HDLC are designed to work in back to back connections and do not require a middle device but Frame Relay is designed to have some kind of switch in the middle.

HTH

Rick

[desai.jaideep]

Hi Rick.

Please share with us, how this can be done with 2 routers.This is something new for me and I haven't done it before.

Thanks and regards

JD

[ashishpanda]

Thanks alot guys...

Ijust tested with back to back with 2 routers...

The changes need are no keepalive onthe serial interface...This stops the LMI transfer...

Ashish

[Richard Burts]

JD

This link should give you the information to configure frame relay back to back:

http://www.cisco.com/en/US/tech/tk713/tk237/technologies_configuration_example09186a0080094a3c.shtml

Note that there is a physical DCE and a Frame Relay DCE. The physical DCE is determined by the cable and must supply clock rate. The Frame Relay DCE is a logical assignment indicating who will supply LMI. There is no requirement that the physical DCE must be the logical DCE. So R1 might be configured as physical DCE and R2 be configured as Frame Relay DCE.

HTH

Rick

[jackyoung]

You can try to add broadcast at frame-relay.