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Frame Relay connectivity

a.maldonado
Level 1
Level 1

I have two 2500 and one 3600 connected together via Frame Relay. I configured the 3600 to be a FR switch and is providing clocking on each interface to each of the 2500's. The 2500 are the DTE's. The interfaces are X.21 and they are connected back to back with the 3600 using a DCE cable. The interfaces show they are up, the LMI is up at both ends but I cant ping from one 2500 to the other, or to the LAN interface on each of the 2500's. Sh cdp neigh does not show any of the routers, and the ip route command only shows the subnets directly attached to each router.

Does anyone have any idea what I am doing wrong?

Many thanks.

Arturo Maldonado

21 Replies 21

rlcarr
Level 1
Level 1

Did you map your 2500 interfaces to the PVCs that you created on the 3600? What is the routing protocol you are running?

You may want to post your config.

I am sure I mapped them before but I have remove the maping because I was trying something else. Anyway, this is the current config of the three routers.

Config from Router_3 (Frame Relay switch)

interface Serial1/0

description link to Router_1

ip address 15.1.1.10 255.255.255.252

encapsulation frame-relay

no ip route-cache

no ip mroute-cache

bandwidth 1000

clockrate 1000

frame-relay intf-type dce

frame-relay route 30 interface Serial1/1 40

!

interface Serial1/1

description link to Router_2

ip address 15.1.1.6 255.255.255.252

encapsulation frame-relay

bandwidth 500

clockrate 500

frame-relay intf-type dce

!

Config from Router_1

interface Serial1

ip address 15.1.1.9 255.255.255.252

encapsulation frame-relay

no ip mroute-cache

bandwidth 1000

frame-relay map ip 15.1.1.10 30

frame-relay interface-dlci 30

Config from Router_2

interface Serial1

ip address 15.1.1.5 255.255.255.252

encapsulation frame-relay

bandwidth 500

frame-relay interface-dlci 40

!

Please note that routers 1 and 2 are the 2500s and router 3 is the 3600 con figured as FR switch.

Many thanks.

Arturo.

looks to me like you need to map dlci 40 back to dlci 30. so on the 3600 do this under int s1/1

frame-relay route 40 interface Serial1/0 30

thisisshanky
Level 11
Level 11

What does a show frame-relay map command reveal on either routers ???

Once you give a "debug frame-relay packet", do you get any encapsulation failures ??

I would recommend, not using the debug command during peak hours..

Sankar Nair
UC Solutions Architect
Pacific Northwest | CDW
CCIE Collaboration #17135 Emeritus

Hi!,

I am sorry for replying late but I was away for a week and just returned today.

Answering your questions, please see the output of your recommended commands.

Router_1#sh frame-relay map

Serial1 (up): ip 15.1.1.10 dlci 30(0x1E,0x4E0), static,

CISCO, status defined, inactive

Router_1#debug frame-relay packet

Frame Relay packet debugging is on

Router_1#

Serial1: broadcast search

Serial1:encaps failed on broadcast for link 7(IP)

Serial1: broadcast search

Serial1:encaps failed on broadcast for link 7(IP)

Router_2#sh frame-relay map

Router_2#debug frame-relay packet

Frame Relay packet debugging is on

Router_2#

Serial1: broadcast search

Serial1:encaps failed on broadcast for link 7(IP)

Serial1: broadcast search

Serial1:encaps failed on broadcast for link 7(IP)

Router_3#sh frame-relay map

Router_3#debug frame-relay packet

Frame Relay packet debugging is on

Router_3#

4w0d: Serial1/1: broadcast search

4w0d: Serial1/1:encaps failed on broadcast for link 7(IP)

4w0d: Serial1/0: broadcast search

4w0d: Serial1/0:encaps failed on broadcast for link 7(IP)

Please note that Routers 1 and 2 are the 2500s which are the DTEs. Router 3 is the DEC configured as a Frame relay switch.

Many thanks.

Arturo

Hello Arturo,

It looks like, you got a static map on Router 1 for Router 2s ip address (15.1.1.10)

But on Router 2, you do not seem to have an ip mapping. You will need to have a similar mapping for Router 1.

command is "frame-relay map ip broadcast (note that you should map the remote ip address to the local dlci)

You seem to have encapsulation failure errors on the debug output, due to this lack of mapping.

Hope that helps!

frame-relay

Sankar Nair
UC Solutions Architect
Pacific Northwest | CDW
CCIE Collaboration #17135 Emeritus

you are missing the frame-relay route statement on the second interface in the switch. You also did not show if you set the frame-relay switch global command. takes the ip addresses off the switch interfaces, you are building a layer 2 device not a router.

On the switch do a show frame route and see if you have matching routes that point to each other like the first two lines here from my 1720. That tells you if the switch is properly configured.

frsw#sh frame route

Input Intf Input Dlci Output Intf Output Dlci Status

Serial0 201 Serial1 102 active

Serial1 102 Serial0 201 active

Serial1 103 Serial2 301 active

Serial1 105 Serial3 501 active

Serial2 301 Serial1 103 active

Serial3 501 Serial1 105 active

Richard,

The switch interfaces now look like this.

interface Serial1/0

description link to Router_1

no ip address

encapsulation frame-relay

no ip route-cache

no ip mroute-cache

bandwidth 1000

clockrate 1000

frame-relay intf-type dce

frame-relay route 30 interface Serial1/1 40

!

interface Serial1/1

description link to Router_2

no ip address

encapsulation frame-relay

bandwidth 500

clockrate 500

frame-relay intf-type dce

frame-relay route 40 interface Serial1/0 30

The router was already configured with the frame-relay switching command.

After I added the frame-relay route statement to the second interface in the switch I could see the following.

Router_3#sh frame route

Input Intf Input Dlci Output Intf Output Dlci Status

Serial1/0 30 Serial1/1 40 active

Serial1/1 40 Serial1/0 30 active

However, I can't ping from Router_1 to Router_2 and viceversa. They are configured in a 30 bit subnet nor can they see each other with the show cdp neigh command.

Any more ideas?

Many thanks.

Arturo.

Hi! Sankar,

I added the maping you suggested and now the interfaces look like this.

These are the interfaces in the router configured as a frame relay switch.

interface Serial1/0

description link to Router_1

no ip address

encapsulation frame-relay

no ip route-cache

no ip mroute-cache

bandwidth 1000

clockrate 1000

frame-relay intf-type dce

frame-relay route 30 interface Serial1/1 40

!

interface Serial1/1

description link to Router_2

no ip address

encapsulation frame-relay

bandwidth 500

clockrate 500

frame-relay intf-type dce

frame-relay route 40 interface Serial1/0 30

This is the interface in Router_1

interface Serial1

ip address 15.1.1.6 255.255.255.252

encapsulation frame-relay

no ip mroute-cache

bandwidth 1000

frame-relay map ip 15.1.1.5 30 broadcast

frame-relay interface-dlci 30

This is the interface in Router_2

interface Serial1

ip address 15.1.1.5 255.255.255.252

encapsulation frame-relay

bandwidth 500

frame-relay map ip 15.1.1.6 40 broadcast

frame-relay interface-dlci 40

There don't seem to be encapsulation errors anymore.

Router_2#debug frame-relay packet

Frame Relay packet debugging is on

Router_2#

Serial1: broadcast search

Serial1: Broadcast on DLCI 40 link 7

Serial1(o): dlci 40(0x881), pkt type 0x800(IP), datagramsize 64

Serial1(o): dlci 40(0x881), pkt type 0x800(IP), datagramsize 64

broadcast dequeue

Serial1(o):Pkt sent on dlci 40(0x881), pkt type 0x800(IP), datagramsize 64

broadcast dequeue

Serial1(o):Pkt sent on dlci 40(0x881), pkt type 0x800(IP), datagramsize 64

Serial1(i): dlci 40(0x881), pkt type 0x800, datagramsize 64

The problem still is that I can't ping between the FR interfaces in router 1 and 2.

Any more ideas?

Many thanks for your help.

Arturo.

drogell
Level 1
Level 1

What code are you running because I noticed in some codes dcp is not enabled by default you will have to manually enable it. Also I do not see any routing protocols configured static or dynamic, so without a routing protocol you will not be able to ping your neibors lan network.

hth

Dennis

Dennis,

Routers 1 and 2 can see each other via another serial HDLC interface. The router configured as a switch can see another router directly attached to its ethernet interface. The problem is that neither Router 1 or 2 can see Router 3 (the switch) via the FR interfaces.

Router 1 and 2 are running EIGRP, Router 3 had EIGRP as well but I just removed it because I wasn't sure if it should have it since it is only perfoming as a switch. What do you say?

Thanks for your help.

Arturo.

Do a show frame pvc and sh fram lmi on rtr1 and rtr2. That will tell you if they are talking to the fram switch and what pvc it has configured on those interfaces. Also check the lmi-type in the switch versus each router. The default changed at some point in the past and if rtr1 and2 are older they might be using a different lmi type.

Richard,

I think both routers are talking to the switch. See below the output of the commands.

Router_1#sh frame pvc

PVC Statistics for interface Serial1 (Frame Relay DTE)

DLCI = 30, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial1

input pkts 391 output pkts 421 in bytes 26206

out bytes 29954 dropped pkts 1 in FECN pkts 0

in BECN pkts 0 out FECN pkts 0 out BECN pkts 0

in DE pkts 0 out DE pkts 0

out bcast pkts 177 out bcast bytes 11328

pvc create time 3w1d, last time pvc status changed 00:09:00

Router_1#

Router_1#

Router_1#sh frame lmi

LMI Statistics for interface Serial1 (Frame Relay DTE) LMI TYPE = CISCO

Invalid Unnumbered info 0 Invalid Prot Disc 0

Invalid dummy Call Ref 0 Invalid Msg Type 0

Invalid Status Message 0 Invalid Lock Shift 0

Invalid Information ID 0 Invalid Report IE Len 0

Invalid Report Request 0 Invalid Keep IE Len 0

Num Status Enq. Sent 147359 Num Status msgs Rcvd 147358

Num Update Status Rcvd 0 Num Status Timeouts 1

Router_2#sh frame pvc

PVC Statistics for interface Serial1 (Frame Relay DTE)

DLCI = 40, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial1

input pkts 419 output pkts 380 in bytes 29724

out bytes 25102 dropped pkts 0 in FECN pkts 0

in BECN pkts 0 out FECN pkts 0 out BECN pkts 0

in DE pkts 0 out DE pkts 0

out bcast pkts 349 out bcast bytes 22064

pvc create time 2w3d, last time pvc status changed 00:06:26

Router_2#

Router_2#

Router_2#sh frame lmi

LMI Statistics for interface Serial1 (Frame Relay DTE) LMI TYPE = CISCO

Invalid Unnumbered info 0 Invalid Prot Disc 0

Invalid dummy Call Ref 0 Invalid Msg Type 0

Invalid Status Message 0 Invalid Lock Shift 0

Invalid Information ID 0 Invalid Report IE Len 0

Invalid Report Request 0 Invalid Keep IE Len 0

Num Status Enq. Sent 146962 Num Status msgs Rcvd 146963

Num Update Status Rcvd 0 Num Status Timeouts 0

Router_2#

The lmi in both interfaces in the switch are Cisco same as in the routers 1 and 2.

Thanks for your time.

Arturo.

Aisco router configured as a switch can also be used as a regular router I do bit all the time in the lab, so configuring eigrp on the switch should not be a problem.\

Dennis

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