EIGRP over Frame relay configuration in GNS3: example in Wendell Odom CCNP ROUTE book

aocferreira

Hello guys,

Please note below attached pictures.
First picture is present in CCNP ROUTE book. I have created this topology in GNS3 (pic 2) in order to see how EIGRP works over a frame relay network. Anyway, I don't know what's going wrong with this configuration but it's not working 100% (my feeling is that there is some kind of an error in mapping in FR switch).

Mapping:

Port: DLCI Port: DLCI
1:101 3:1001
1:102 4:1003
2:103 3:1002
2:104 4:1004

Below, you have important configuration in router B1 for this scenario. The other routers follow same logic.

interface FastEthernet0/0
ip address 10.11.1.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0
no ip address
encapsulation frame-relay
clock rate 2000000
!
interface Serial0/0.1 point-to-point
ip address 10.1.1.2 255.255.255.0
snmp trap link-status
frame-relay interface-dlci 101
!
interface Serial0/0.2 point-to-point
ip address 10.1.2.2 255.255.255.0
snmp trap link-status
frame-relay interface-dlci 102
!
router eigrp 1
network 10.0.0.0
auto-summary

B1#show ip eigrp neighbors
IP-EIGRP neighbors for process 1
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
1 10.1.1.1 Se0/0.1 13 00:00:52 645 3870 0 19
0 10.1.2.1 Se0/0.2 13 00:00:52 48 288 0 19

Ping works: 10.1.2.2, 10.1.2.1, 10.1.2.5, 10.1.1.5,
Ping not working: 10.1.1.2, 10.1.1.1, 10.1.2.6, 10.1.1.6

Pinging 10.1.1.1 the success rate is ALWAYS 60% (3/5).

What is possibly going wrong here? Split horizon problems? I thought about that, and I have disabled split horizon in all subinterfaces for 4 routers but same thing happening (although I think that split horizon problems only affect multi-point subinterfaces, but not sure...)

Thanks in advance for your help.

Please let me know if any missing config is needed.

Br
André

Jackace

Are you using the GNS3 FR switch or are you configuring a router to be FR switch? I ask because the FR switch in GNS3 can give weird results. I always just configure a router as a FR switch and have never had problems.

aocferreira

Hi,

I'm using the GNS3 FR switch.

Jackace

Try replacing it with a router configured as a FR switch and see if you have the same issues.

aocferreira

Hi Jackace,

I removed FR switch and placed a router but it's also not working. Are there any problems if I remove the FR switch, insert and configure the router? Or do I have to configure everything from the beginning ? (B1, B2, WAN1, WAN2)

aocferreira

This is output of "show frame-relay route":

FRSW#show frame-relay route
Input Intf Input Dlci Output Intf Output Dlci Status
Serial0/0 101 Serial0/2 1001 active
Serial0/0 102 Serial0/3 1003 active
Serial0/1 103 Serial0/2 1002 active
Serial0/1 104 Serial0/3 1004 active
Serial0/2 1001 Serial0/0 101 active
Serial0/2 1002 Serial0/1 103 active
Serial0/3 1003 Serial0/0 102 active
Serial0/3 1004 Serial0/1 104 active

Jackace

aocferreira wrote: »

Hi Jackace,

I removed FR switch and placed a router but it's also not working. Are there any problems if I remove the FR switch, insert and configure the router? Or do I have to configure everything from the beginning ? (B1, B2, WAN1, WAN2)

If you remove the GNS3 FR switch and put a properly configured router in it should work. I did not verify the rest of your network is correct however so it very well could be something else was configured wrong and it wasn't the GNS3 FR switch.

Jackace

I just built your lab in GNS3 based on the picture from the text and I'm getting full connectivity. Did you make sure you put the "no ip split-horizon eigrp" command on the physical interface and not the sub interface?

Edit- also check for any shutdown interfaces.

Edit 2 - Below is my relevant config for B1 and my FR switch

interface Loopback0
ip address 10.11.1.1 255.255.255.0
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/0
no ip address
encapsulation frame-relay IETF
no ip split-horizon eigrp 1
clock rate 2000000
!
interface Serial0/0.103 point-to-point
ip address 10.1.1.2 255.255.255.252
snmp trap link-status
frame-relay interface-dlci 103 IETF protocol ip 10.1.1.1
!
interface Serial0/0.104 point-to-point
ip address 10.1.2.2 255.255.255.252
snmp trap link-status
frame-relay interface-dlci 104 IETF protocol ip 10.1.2.1
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
router eigrp 1
network 10.0.0.0
auto-summary



frame-relay switching
!
interface Serial0/0
no ip address
encapsulation frame-relay IETF
clock rate 2000000
frame-relay intf-type dce
frame-relay route 103 interface Serial0/2 301
frame-relay route 104 interface Serial0/3 401
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/1
no ip address
encapsulation frame-relay IETF
clock rate 2000000
frame-relay intf-type dce
frame-relay route 203 interface Serial0/2 302
frame-relay route 204 interface Serial0/3 402
!
interface Serial0/2
no ip address
encapsulation frame-relay IETF
clock rate 2000000
frame-relay intf-type dce
frame-relay route 301 interface Serial0/0 103
frame-relay route 302 interface Serial0/1 203
!
interface Serial0/3
no ip address
encapsulation frame-relay IETF
clock rate 2000000
frame-relay intf-type dce
frame-relay route 401 interface Serial0/0 104
frame-relay route 402 interface Serial0/1 204

aocferreira

There are somethings that are bugging me here. I have replaced the router for the FR switch and cannot understand why:

1) From router B1, I cannot ping subinterface s0/0.1 but s0/0.2 works ok:

B1#ping 10.1.2.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.2.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 8/23/60 ms
B1#ping 10.1.1.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.1.2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)

What can be the cause for this?

2) If I try to ping 10.9.1.2 (WAN2 LAN) it works, but 10.9.1.1 (WAN1 LAN) it does not work.

This is ip routing table for B1:

10.0.0.0/24 is subnetted, 5 subnets
C 10.11.1.0 is directly connected, FastEthernet0/0
D 10.9.1.0 [90/2195456] via 10.1.2.1, 00:08:36, Serial0/0.2
[90/2195456] via 10.1.1.1, 00:08:36, Serial0/0.1
D 10.12.1.0 [90/2707456] via 10.1.2.1, 00:08:33, Serial0/0.2
[90/2707456] via 10.1.1.1, 00:08:33, Serial0/0.1
C 10.1.2.0 is directly connected, Serial0/0.2
C 10.1.1.0 is directly connected, Serial0/0.1

3) I must confess I need some review on CCNA topics, can you explain why did you configure frame-relay with ietf paramenter? Is this really necessary? Because I did not use it.

Jackace

Is the GNS3 capture above exactly how you have everything addressed and connected?

If so then you have the same subnet off WAN1 and WAN2, but they are not connected. The picture from the book you are trying to recreate has the LAN interfaces on both those routers connected. Your GNS3 topology does not. You however used the same IP addressing as the book and those 2 interfaces are in the same subnet, but are not connected. You created a routing black hole.

aocferreira

Hi,

Good point, but with fa0/0 interfaces connected same thing happens. From B1 point of view, I can ping 10.9.1.2 but not 10.9.1.1 !

It seems a dead end case here... I believe I will quit trying to set this up! The neighbor relationships are OK in four routers, topology tables and IP routing tables mention all sub-nets, but in some cases ping does not work

And do you have any idea why pinging s0/0.2 does not work and s0/0.1 works good? (From B1).

Anyway, thanks a lot for your help.

Jackace

Without seeing all your configs it's hard to tell exactly what you have wrong. You can always try using traceroute and see where your traffic is going hop by hop and see where it is dying. Based on your routing table above it looks like EIGRP is doing equal cost load balancing to the LAN subnet so that explains your earlier issue with 3/5 pings succeeding.

aocferreira

OK, nevermind... I will proceed with my study and then I will come back to this scenario.

But note for router WAN1:

show ip route
D 10.11.1.0 [90/2195456] via 10.1.2.2, 00:07:49, Serial0/0.1

ping 10.11.1.1
Sending 5, 100-byte ICMP Echos to 10.11.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/14/32 ms

ping 10.1.2.2 (next hop for 10.11.1.0/24.... and IP address that's advertizing this sub-net)
Sending 5, 100-byte ICMP Echos to 10.1.2.2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)

Strange imo...

Thanks a lot! If somehow this starts to work, I will update this thread

Jackace

You have something very weird configured. 10.1.2.2 is not a subnet connected to the WAN1 router. Based on the pictures in your first post the route should have been learned from 10.1.1.2. Looks like you might have some IP addressing issues to me.