Friday, November 5, 2010

Complete Frame Relay Lab Setup with T1 WICs

I set up a very simple frame-relay Cisco lab today using the following equipment:

Cisco 1841 router with a WIC 1DSU-T1 V2 card (acting as DTE #1 - TOP)
Cisco 1841 router with a VWIC2-2MFT-T1/E1 card (acting as DTE #2 - SMALL)
Cisco 3825 router with a VWIC2-2MFT-T1/E1 card (acting as DTE #3 - BOTTOM)
Cisco 3640 router with a few WIC 1DSU T1 card (acting as DCE - frame relay switch - FRSWITCH)

NOTE!  There are no serial cables involved here.  These are all T1 WICs with RJ45 connections.  See this post if you need to create T1 crossover cables for this setup.  I had a lot of trouble setting this up properly due to lack of coherent information online regarding the T1 card configuration on the router acting as a frame relay switch (not to mention it was my first attempt at setting up a frame relay network).

DOUBLE NOTE!!  These exact instructions won't work using serial cables!  If you are using serial cables, there are plenty of other instructions out there to follow.

First of all, here is the diagram of what I ended up creating:

The router named FRSWITCH acts as a frame relay switch (the telco's network), and the other two routers act as two endpoints we need to connect via frame relay!  I left the switch connected to BOTTOM from the last lab I created; it doesn't affect this configuration at all.

I'm going to assume all the cables are made, tested, and connected properly as shown in the diagram above.

Let's start by programming the FRSWITCH router:

FRSWITCH#configure terminal
FRSWITCH(config)#frame-relay switching
FRSWITCH(config)#interface s0/0
FRSWITCH(config-if)#encapsulation frame-relay
FRSWITCH(config-if)#no ip mroute-cache
FRSWITCH(config-if)#frame-relay intf-type dce
FRSWITCH(config-if)#frame-relay route 100 interface s0/1 101
FRSWITCH(config-if)#frame-relay route 102 interface s3/0 101
----- This last command tells the router to take frames with DLCI 102 and send them out s3/0 re-tagged with DLCI 101 (so that the destination knows where they came from).  These two commands, along with their counterparts a few lines down, actually create the PVCs.

FRSWITCH(config-if)#no shutdown
FRSWITCH(config-if)#interface s0/1
FRSWITCH(config-if)#encapsulation frame-relay
FRSWITCH(config-if)#frame-relay intf-type dce
----- This command doesn't have anything to do with clocking or serial cables - it just affects LMI functions.

FRSWITCH(config-if)#frame-relay route 101 interface s0/0 100
FRSWITCH(config-if)#frame-relay route 102 interface s3/0 100
FRSWITCH(config-if)#no shutdown

NOTE!  At no point in the FRSWITCH configuration do you have to specify service-module T1 settings.

Next, I set up BOTTOM as a DTE:

BOTTOM#configure terminal
BOTTOM(config)#card type t1 0 0
BOTTOM(config)#controller t1 0/0/0
BOTTOM(config-controller)#channel-group 0 timeslots 1-24 speed 64
BOTTOM(config-controller)#interface s0/0/0:0
BOTTOM(config-if)#encapsulation frame-relay
BOTTOM(config-if)#no shutdown

That finishes up the basic frame-relay setup on BOTTOM.  Next I did the same thing to SMALL, just changing the IP address:

SMALL#configure terminal
SMALL(config)#card type t1 0 0
SMALL(config)#controller t1 0/0/0
SMALL(config-controller)#channel-group 0 timeslots 1-24 speed 64
SMALL(config-controller)#interface s0/0/0:0
SMALL(config-if)#encapsulation frame-relay
SMALL(config-if)#ip address
SMALL(config-if)#no shutdown

Follow the steps above again on TOP, and all 3 routers should have no trouble pinging across the network!  I also configured the Ethernet interfaces shown on the routers, then configured EIGRP, allowing communication between all subnets on the diagram, but I won't cram that into this post.

NOTE!  You can see details on how Frame Relay is configured by running "show frame-relay pvc" or "show frame-relay map" on any of the DTE routers.

Let me know if you run into any problems or have any questions - hopefully this helps document the process of using the T1 WICs for frame relay lab connections.


  1. Hi, just a comment...
    You don't need the channel-group command for the WIC 1DSU-T1 V2 card on the TOP router! This should be enough:
    interface Serial0/0/0
    bandwidth 1536
    encapsulation frame-relay IETF
    service-module t1 timeslots 1-24
    ip address
    no shutdown

  2. So what interface on the FR Switch, is the on?

  3. Oh! A big thanks to the American Musicological Society for uploading so much information. I felt it very interesting, Opera has a class , this will remain as a part of culture.