subinterfaces – Fredrik Holmberg / Network Consultant Thu, 10 Nov 2016 19:39:24 +0000 en-US hourly 1 https://wordpress.org/?v=4.7.3 /wp-content/uploads/2016/04/cropped-2601-32x32.png subinterfaces – Fredrik Holmberg / 32 32 Frame Relay switching and point-to-point subinterfaces /2012/03/frame-relay-switching-and-point-to-point-subinterfaces/ /2012/03/frame-relay-switching-and-point-to-point-subinterfaces/#respond Sun, 25 Mar 2012 15:41:00 +0000 Having browsed through half the Internet without finding any decent documentation on how to do this, I gave up on Google and put together something myself. Hopefully it can be useful for other networking students.

I’m doing a lab for Cisco CCNP ROUTE where you’re supposed to set up OSPF over a Frame Relay (NBMA) hub-and-spoke topology with a headquarter and two remote sites. All subinterfaces must be configured as point-to-point. This is how you configure the Frame Relay part.

Topology:

fr_cloud

  • DLCI 102 and 201 connecting R1_HQ and R2_EAST.
  • DLCI 103 and 301 connecting R1_HQ and R4_WEST.
  • R3_FR provides clocking signals (DCE) to the connected Frame Relay routers (DTE).

Configuration of the Frame Relay switch, R3_FR:

frame-relay switching
interface Serial0/0
 bandwidth 64
 no ip address
 encapsulation frame-relay IETF
 no ip route-cache
 clock rate 64000
 frame-relay intf-type dce
 frame-relay route 102 interface Serial0/1 201
 frame-relay route 103 interface Serial0/2 301
interface Serial0/1
 bandwidth 64
 no ip address
 encapsulation frame-relay IETF
 no ip route-cache
 clock rate 64000
 frame-relay intf-type dce
 frame-relay route 201 interface Serial0/0 102
interface Serial0/2
 bandwidth 64
 no ip address
 encapsulation frame-relay IETF
 no ip route-cache
 clock rate 64000
 frame-relay intf-type dce
 frame-relay route 301 interface Serial0/0 103

Configuring the R1_HQ router:

interface Serial0/0
bandwidth 64
no ip address
encapsulation frame-relay IETF
interface Serial0/0.102 point-to-point
ip address 10.1.1.1 255.255.255.252
frame-relay interface-dlci 102
interface Serial0/0.103 point-to-point
ip address 10.1.1.5 255.255.255.252
frame-relay interface-dlci 103

Configuring the R2_EAST router:

interface Serial0/0
bandwidth 64
no ip address
encapsulation frame-relay IETF
interface Serial0/0.201 point-to-point
ip address 10.1.1.2 255.255.255.252
frame-relay interface-dlci 201

Configuring the R4_WEST router:

interface Serial0/0
 bandwidth 64
 no ip address
 encapsulation frame-relay IETF
interface Serial0/0.301 point-to-point
 ip address 10.1.1.6 255.255.255.252
 frame-relay interface-dlci 301

HQ router can now ping both the EAST and WEST router.

Here’s how the Frame Relay switch see the topology:

R3_FR#show frame-relay route
Input Intf      Input Dlci      Output Intf     Output Dlci     Status
Serial0/0       102             Serial0/1       201             active
Serial0/0       103             Serial0/2       301             active
Serial0/1       201             Serial0/0       102             active
Serial0/2       301             Serial0/0       103             active

For more information check out “Comprehensive Guide to Configuring and Troubleshooting Frame Relay”:
http://www.cisco.com/en/US/tech/tk713/tk237/technologies_tech_note09186a008014f8a7.shtml

Similar services are also provided professionally through my Consulting Services.

]]> /2012/03/frame-relay-switching-and-point-to-point-subinterfaces/feed/ 0