Cisco CCNP and CCIE Study Notes

Consider two routers connected back-to-back like this

Router1 ---- [Frame Relay Cloud] ---- Router2

Here is the relevant config for the routers

Router1

interface Serial2/0
 ip address 150.150.12.1 255.255.255.0
 encapsulation frame-relay
 no keepalive
 no fair-queue
 frame-relay interface-dlci 102

Router2

interface Serial2/0
 ip address 150.150.12.2 255.255.255.0
 encapsulation frame-relay
 no keepalive
 no fair-queue
 frame-relay interface-dlci 201

The two routers can successfully ping over the frame relay interfaces.

Now, we wish to run CHAP between the two routers over the frame relay link for security reasons. How will the config need to be modified to make that happen? Assume that the usernames to be used for CHAP are the router hostnames itself and the password for both routers is "cisco".

Consider two routers connected back-to-back like this

Router1 ---- [Frame Relay Cloud] ---- Router2

Assume that the frame relay switch between the two routers has been correctly configured and is properly functioning.

Here is the relevant configuration for the routers

Router1

interface Serial2/0
 ip address 150.150.12.1 255.255.255.0
 encapsulation frame-relay
 no keepalive
 no fair-queue
 frame-relay interface-dlci 102

Router2

interface Serial2/0
 ip address 150.150.12.2 255.255.255.0
 encapsulation frame-relay
 no keepalive
 no fair-queue
 frame-relay interface-dlci 201

The two routers can ping each other on these serial interfaces. However, when an attempt is made on each of the routers to ping its own serial interface, the pings fail. Is there some way pings on each router to its own serial interface can be made to work? If so, how? If not, explain why that is not possible.