How to configure a Cisco router to be a frame relay switch

If you are studying for the TSHOOT exam, it is a good idea to familiarize yourself with the topology. I've been working on creating a lab that mocks the TSHOOT topology, and it has forced me to recall how to setup a Cisco router to act like a Frame Relay switch. 

Here is the topology that I've built. As you can see, it closely resembles the topology that Cisco has provided on their site. Since their doc doesn't provide specific DLCIs, I've used the most logical numbers I could think of.

The first step in configuring a Cisco router to act like a frame relay switch is to enable frame relay switching:

FR(config)#frame-relay switching 

Once enabled, you then configure the serial interfaces connected to the other routers.

interface Serial0/0
 description Link to R4
 no ip address
 encapsulation frame-relay
 clock rate 64000
 no frame-relay inverse-arp
 frame-relay lmi-type ansi
 frame-relay intf-type dce
 frame-relay route 403 interface Serial0/1 304
!
interface Serial0/1
 description Link to R3
 no ip address
 encapsulation frame-relay
 clock rate 64000
 no frame-relay inverse-arp
 frame-relay lmi-type ansi
 frame-relay intf-type dce
 frame-relay route 302 interface Serial0/2 203
 frame-relay route 304 interface Serial0/0 403
!
interface Serial0/2
 description Link to R2
 no ip address
 encapsulation frame-relay
 clock rate 64000
 no frame-relay inverse-arp
 frame-relay lmi-type ansi
 frame-relay intf-type dce
 frame-relay route 201 interface Serial0/3 102
 frame-relay route 203 interface Serial0/1 302
!
interface Serial0/3
 description Link to R1
 no ip address
 encapsulation frame-relay
 clock rate 64000
 no frame-relay inverse-arp
 frame-relay lmi-type ansi
 frame-relay intf-type dce
 frame-relay route 102 interface Serial0/2 201

Then all you need to do is configure the other routers and connect them to your "switch". Here are the configs for the other router serial interfaces for reference:

!R1
interface Serial0/0
 no ip address
 encapsulation frame-relay
 no frame-relay inverse-arp
 frame-relay lmi-type ansi
!
interface Serial0/0.12 point-to-point
 ip address 10.1.1.1 255.255.255.252
 frame-relay interface-dlci 102 

!R2
interface Serial0/0
 no ip address
 encapsulation frame-relay
 no frame-relay inverse-arp
 frame-relay lmi-type ansi
!
interface Serial0/0.12 point-to-point
 ip address 10.1.1.2 255.255.255.252
 frame-relay interface-dlci 201   
!
interface Serial0/0.23 point-to-point
 ip address 10.1.1.5 255.255.255.252
 frame-relay interface-dlci 203   

!R3
interface Serial0/0
 no ip address
 encapsulation frame-relay
 no frame-relay inverse-arp
 frame-relay lmi-type ansi
!
interface Serial0/0.23 point-to-point
 ip address 10.1.1.6 255.255.255.252
 frame-relay interface-dlci 302   
!
interface Serial0/0.34 point-to-point
 ip address 10.1.1.9 255.255.255.252
 frame-relay interface-dlci 304 

!R4
interface Serial0/0
 no ip address
 encapsulation frame-relay
 no frame-relay inverse-arp
 frame-relay lmi-type ansi
!
interface Serial0/0.34 point-to-point
 ip address 10.1.1.10 255.255.255.252
 frame-relay interface-dlci 403   

References used for this configuration are as follows:

Cisco Press Book - Cisco Frame Relay Configurations Chapter (ciscopress.com)

Comprehensive Guide to Configuring and Troubleshooting Frame Relay (cisco.com)

TSHOOT Topology PDF (cisco.com)