RouterGeek

When would you need this: When are setting up your own Frame-Relay network. Usually, it is used for lab setup.

Special Requirements: A Cisco router with at least two serial interfaces.

This setup is mainly done for lab experiments because operating a Cisco router as an actual Frame-Relay Switch requires alot of Serial interfaces.

As a start, you need to keep in mind that when a Cisco router operates as a frame-relay switch, it wil stop operating as an IP router. No IP routing process will occur during the Frame-Relay operations. The router will become exclusively a frame-relay switch.

Before you start configuration, draw the network topology and mark on it the numbers of DLCIs that will be used. What the frame-realy switch does is receiving a frame with a certain DLCI number from one interface and forwarding it to a different interface after assigning it a different DLCI number. With that said, now we move on to the configuration:

1. Enable Frame-Relay Switching operation on the router's global configuration:

Router(config)#frame-relay switching

2.Configure the two (or more) interfaces that will participate in the frame-relay switching process

Router(config-if)#no ip address

Router(config-if)#encapsulation frame-relay

Router(config-if)#logging event subif-link-status

Router(config-if)#logging event dlci-status-change

Router(config-if)#clock rate CLKRT

Router(config-if)#no frame-relay inverse-arp

Router(config-if)#frame-realy inft-type dce

where CLKRT is the clock rate of your choice (64000 is a good choice)

Now come the frame-relay routing configuration on the same interface,

Router(config-if)#frame-relay route INDLCI interface serial INTNO OUTDLCI

where,

INDLCI is the DLCI number of the incoming frame

OUTDLCI is the DLCI number that will be assigned to the outgoing frame

INTNO is the serial inetrface number to which the frame will be forwarded to be sent out of the router.

Repeat the frame-realy routing command for as much DLCIs as you plan to be passing through this interface.

3. After completing the steps of configuration for one of the interfaces in step 2, repeat step 2 on each serial interface you want to be part of the frame-relay swtiching process.

Verification and Troubleshooting:

Use the following command to find out the status of each route you have configured on the frame-relay switch:

Router#show frame-realy route