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New Member

Frame Relay Detection

Dear all,

I want to ask if I had a frame relay VC between two routers in a frame relay cloud , and these two routers are not connecting to the same frame relay switch , if one router goes down did the other router will sense that the router is down in layer 2 ? ?

as I know frame relay lmi's are only between frame relay switch and the router and if one goes down the other will not detect that am i right or not ?

thanx in advance,

New Member

Re: Frame Relay Detection


the answere is yes.The router on the other end should get the information over the LMI-protocol

that the "pvc" has changed to inactive because the information is transfered through the FR-network. This is at least the case for FR-networks which are builded up by Cisco FR-switches.

regards Ulrich

New Member

Re: Frame Relay Detection

It's depending of the Frame Relay implementation at the carrier level.

To be sure you can implement FrameRelay keepalive on PVCs at your routers level.

This is available in IOS 12.1 train.

On the 2 routers which are endding a FR PVC :

1. create a map-class frame relay (global config):

map-class frame-relay NAME

frame-relay end-to-end keepalive mode bidirectional

2. apply it on the FR subinterface

interface serialX.Y

frame-relay class NAME