Frame-Relay

Just for the record, I never liked Frame-Relay. It's old and tired and every connection should be a metro ethernet connection in my opinion.... well something better than this. But the reason I am writing this and documenting the setup of a very basic Frame-Relay connection is because it's something that is still asked about and test questions want you to be able to configure it.

Ok Here goes - We have three routers (rack1r1, rack1r2 and rack1r6) each connecting to a Frame Switch (fsw) on a different serial interface. The frame router is essentially any old router with a few serial connections and a global command "frame-relay switching" set.



• Step 1
On the fsw we setup the serial interface to rack1r1 like so:
!
frame_switch#
interface Serial1/0
description connection to r1
no ip address
encapsulation frame-relay <--- This is important
keepalive 20
no fair-queue
serial restart-delay 0
clockrate 64000 <--- Need this too
frame-relay lmi-type ansi <--- another important item
frame-relay intf-type dce <--- this as well
frame-relay route 102 interface Serial1/1 201 <--- This maps traffic into fsw with DLCI 102 to rack1r2 DLCI 201
frame-relay route 103 interface Serial3/2 301 <--- This maps traffic into fsw with DLCI 103 to rack1r6 DLCI 301
!

• Step 2 and 3, you setup the interfaces that connect to rack1r2 and rack1r6. In this case it's Serial1/1 and Serial3/2:
!
frame_switch#
interface Serial1/1
description connection to r2
no ip address
encapsulation frame-relay <--- same
keepalive 20
no fair-queue
serial restart-delay 0
clockrate 64000 <--- same
frame-relay lmi-type ansi <--- same
frame-relay intf-type dce <--- same
frame-relay route 201 interface Serial1/0 102 <--- ok DLCI 201 over to 102 - thats the reverse of rack1r1
frame-relay route 202 interface Serial3/2 302 <--- This is DLCI 202 over to rack1r6 which we configure below

Here is the link to rack1r6:
!
frame_switch#
interface Serial3/2
description connection to r6
no ip address
encapsulation frame-relay <---yup
keepalive 20
no fair-queue
serial restart-delay 0
clockrate 64000 <--- yea
frame-relay lmi-type ansi <--- I know...
frame-relay intf-type dce <--- I know!
frame-relay route 301 interface Serial1/0 103 <--- Reverse again 301 to 103 which is rack1r1
frame-relay route 302 interface Serial1/1 202 <--- Back to rack1r2 on 202

• OK so we have all that in place. We are ready now to configure the interfaces on the routers themselves to make all this happen:



- Starting with rack1r1:
!
rack1r1#
interface Serial0/0
description connection to frameswitch s1/0
ip address 192.168.1.1 255.255.255.248
ip pim dense-mode
encapsulation frame-relay <--- need this here also
keepalive 15
no fair-queue
frame-relay map ip 192.168.1.1 102 broadcast <--- This is in place so you can ping yourself
frame-relay map ip 192.168.1.2 102 broadcast <--- map for traffic destined for rack1r2's ip
frame-relay map ip 192.168.1.3 103 broadcast <--- map for traffic destined for rack1r6's ip
frame-relay lmi-type ansi <--- the options you have here are cisco, ansi and q933a

• OK same thing on the other two routers:
!
rack1r2#
interface Serial0/0
description connection to frameswitch s1/1
ip address 192.168.1.2 255.255.255.248
ip pim dense-mode
encapsulation frame-relay <--- same thing
keepalive 15
no fair-queue
frame-relay map ip 192.168.1.1 201 broadcast
frame-relay map ip 192.168.1.2 201 broadcast <--- This is in place so you can ping yourself
frame-relay map ip 192.168.1.3 202 broadcast
frame-relay lmi-type ansi <--- same
!
rack1r6#
interface Serial0/0
description connection to frameswitch s3/2
ip address 192.168.1.3 255.255.255.248
encapsulation frame-relay <--- same
keepalive 15
no fair-queue
frame-relay map ip 192.168.1.1 301 broadcast
frame-relay map ip 192.168.1.2 302 broadcast
frame-relay map ip 192.168.1.3 301 broadcast <--- This is in place so you can ping yourself

• Ok now that thats all done you should have a working model with the ability from any router to ping the other two and yourself.

Here is what the fsw should look like when you do a "show frame-relay route"

Input Intf Input Dlci Output Intf Output Dlci Status
Serial1/0 102 Serial1/1 201 active
Serial1/0 103 Serial3/2 301 active
Serial1/1 201 Serial1/0 102 active
Serial1/1 202 Serial3/2 302 active
Serial3/2 301 Serial1/0 103 active
Serial3/2 302 Serial1/1 202 active