R&S lab ospf nei challenges

[dchen0999]

Hi, All,

It is flappy and wierd. Anyone can shed some lights?

Thanks.

Senario:

r3 hub s0/0.235 mul use nei statement - r2, r5 spoke s0/0

Problem:

1. r2 and r5 or either r2 or r5 no route from other ospf areas.

2. using "ip os ne p-mp" or "ip os ne br" or "use all physical interfaces" is fine

Note:

// osp r5 no full route

1. change router id from 2.2.5.5 to 5.5.5.5 for all routers. cle ip os proce: not working

2. reboot r3/2/5 routers: not working (r3 sub-int multipoint not working; r3 physical int works)

3. change nei statment to ip os ne p-mp: it works.

4. change from ip os ne p-mp to ip os ne p-p: not working

5. cle ip os pro for r2/3/5: still not working

6. put it back: ip os ne p-mp: it is fine.

7. however, it is required to use nei statement.

[dchen0999]

Thanks Jerry. You are very helpful.

[YANGCCIE4]

Hi,Dear Dchen,

when you are doing lab with ospf over Fram Relay, it is very helpful for your troubleshooting ,if you can check the layer 2 configuration first before check ospf connection, use the following command, sh fram map, deb fram lmi,

Yang

[dchen0999]

Hi Yang,

Correct. Will keep in mind.

FR is relatively easy in CCIE lab and it is my 2nd nature with no fail (excluding typo like wrong submask, ip address, or put it in wrong serial interface) at any time except nei statement not behaving stable as it should be in term of spoke router won't get routes from other ospf areas.

Not sure it is due to different of IOS version in the routers like 12.4 (x-xx)?

Thanks friend.

[dchen0999]

glad to let you know: doing another lab, nei works fine with all routes from other ospf areas coming in to the hub and spoke routers.

thanks Giuseppe, Jerry, Yang for the great help.

========

R3#

interface Serial0/0

no ip address

encapsulation frame-relay

no frame-relay inverse-arp

frame-relay lmi-type cisco

!

interface Serial0/0.345 multipoint

ip address 2.2.11.3 255.255.255.0

ip ospf priority 255

snmp trap link-status

frame-relay map ip 2.2.11.3 304

frame-relay map ip 2.2.11.4 304 broadcast

frame-relay map ip 2.2.11.5 305 broadcast

!

router ospf 1

log-adjacency-changes

network 2.2.3.3 0.0.0.0 area 0

network 2.2.11.3 0.0.0.0 area 11

network 2.2.13.2 0.0.0.0 area 0

network 2.2.31.2 0.0.0.0 area 0

neighbor 2.2.11.4

neighbor 2.2.11.5

-----

R4#

interface Serial0/0

ip address 2.2.11.4 255.255.255.0

encapsulation frame-relay

ip ospf priority 0

frame-relay map ip 2.2.11.3 403 broadcast

frame-relay map ip 2.2.11.4 403

frame-relay map ip 2.2.11.5 403 broadcast

no frame-relay inverse-arp

frame-relay lmi-type cisco

!

router ospf 1

log-adjacency-changes

network 2.2.4.4 0.0.0.0 area 11

network 2.2.11.4 0.0.0.0 area 11

-----

R5#

interface Serial0/0

ip address 2.2.11.5 255.255.255.0

encapsulation frame-relay

ip ospf priority 0

frame-relay map ip 2.2.11.3 503 broadcast

frame-relay map ip 2.2.11.4 503 broadcast

frame-relay map ip 2.2.11.5 503

no frame-relay inverse-arp

frame-relay lmi-type cisco

!

router ospf 1

log-adjacency-changes

network 2.2.5.5 0.0.0.0 area 11

network 2.2.11.5 0.0.0.0 area 11

network 2.2.55.254 0.0.0.0 area 11

[dchen0999]

r4#sh ip rout

2.0.0.0/8 is variably subnetted, 13 subnets, 2 masks

O IA 2.2.8.8/32 [110/66] via 2.2.11.3, 00:00:52, Serial0/0

O IA 2.2.7.7/32 [110/66] via 2.2.11.3, 00:00:52, Serial0/0

O 2.2.5.5/32 [110/65] via 2.2.11.5, 00:00:52, Serial0/0

O IA 2.2.3.3/32 [110/65] via 2.2.11.3, 00:00:52, Serial0/0

O IA 2.2.2.2/32 [110/67] via 2.2.11.3, 00:00:52, Serial0/0

O IA 2.2.12.0/24 [110/66] via 2.2.11.3, 00:00:53, Serial0/0

O IA 2.2.13.0/24 [110/65] via 2.2.11.3, 00:00:53, Serial0/0

O IA 2.2.21.0/24 [110/66] via 2.2.11.3, 00:00:53, Serial0/0

O IA 2.2.31.0/24 [110/65] via 2.2.11.3, 00:00:53, Serial0/0

O 2.2.55.0/24 [110/65] via 2.2.11.5, 00:00:53, Serial0/0

O IA 2.2.100.0/24 [110/66] via 2.2.11.3, 00:00:54, Serial0/0

r5#sh ip rout

2.0.0.0/8 is variably subnetted, 13 subnets, 2 masks

O IA 2.2.8.8/32 [110/66] via 2.2.11.3, 00:01:02, Serial0/0

O IA 2.2.7.7/32 [110/66] via 2.2.11.3, 00:01:02, Serial0/0

O 2.2.4.4/32 [110/65] via 2.2.11.4, 00:01:02, Serial0/0

O IA 2.2.3.3/32 [110/65] via 2.2.11.3, 00:01:02, Serial0/0

O IA 2.2.2.2/32 [110/67] via 2.2.11.3, 00:01:02, Serial0/0

O IA 2.2.12.0/24 [110/66] via 2.2.11.3, 00:01:03, Serial0/0

O IA 2.2.13.0/24 [110/65] via 2.2.11.3, 00:01:03, Serial0/0

O IA 2.2.21.0/24 [110/66] via 2.2.11.3, 00:01:03, Serial0/0

O IA 2.2.31.0/24 [110/65] via 2.2.11.3, 00:01:03, Serial0/0

O IA 2.2.100.0/24 [110/66] via 2.2.11.3, 00:01:03, Serial0/0

r3#sh ip rout

2.0.0.0/8 is variably subnetted, 13 subnets, 2 masks

O 2.2.8.8/32 [110/2] via 2.2.31.1, 00:02:45, FastEthernet0/1

O 2.2.7.7/32 [110/2] via 2.2.13.1, 00:02:45, FastEthernet0/0

O 2.2.5.5/32 [110/65] via 2.2.11.5, 00:01:14, Serial0/0.345

O 2.2.4.4/32 [110/65] via 2.2.11.4, 00:01:14, Serial0/0.345

O 2.2.2.2/32 [110/3] via 2.2.31.1, 00:02:45, FastEthernet0/1

[110/3] via 2.2.13.1, 00:02:45, FastEthernet0/0

O 2.2.12.0/24 [110/2] via 2.2.13.1, 00:02:46, FastEthernet0/0

O 2.2.21.0/24 [110/2] via 2.2.31.1, 00:02:46, FastEthernet0/1

O 2.2.55.0/24 [110/65] via 2.2.11.5, 00:01:16, Serial0/0.345

O 2.2.100.0/24 [110/2] via 2.2.31.1, 00:02:47, FastEthernet0/1

[110/2] via 2.2.13.1, 00:02:47, FastEthernet0/0

----

r3# sh ip os nei

Neighbor ID Pri State Dead Time Address Interface

2.2.8.8 1 FULL/BDR 00:00:36 2.2.31.1 FastEthernet0/

1

2.2.7.7 1 FULL/BDR 00:00:33 2.2.13.1 FastEthernet0/

0

2.2.4.4 0 FULL/DROTHER 00:01:35 2.2.11.4 Serial0/0.345

2.2.5.5 0 FULL/DROTHER 00:01:53 2.2.11.5 Serial0/0.345

r4#sh ip os nei

Neighbor ID Pri State Dead Time Address Interface

2.2.3.3 255 FULL/DR 00:01:40 2.2.11.3 Serial0/0

r5#sh ip os nei

Neighbor ID Pri State Dead Time Address Interface

2.2.3.3 255 FULL/DR 00:01:34 2.2.11.3 Serial0/0

[Giuseppe Larosa]

Hello Dengming,

nice to know that this new lab is working well.

About the first one:

if you compare your sh ip ospf interface with those provided by Jerry you see:

in yours:

>>No designated router on this network

>>No backup designated router on this network

in Jerry's show ip ospf int a DR is seen is on the spoke and it is the hub router.

I cannot say what was the cause of the issue.

Jerry:

thanks for correction I had oversimplified the question of network type for sake of clarity and for lack of time.

Hope to help

Giuseppe

[dchen0999]

Interesting.

1. nice to know that this new lab is working well. //thanks.

2. About the first one:

if you compare your sh ip ospf interface with those provided by Jerry you see:

in yours:

>>No designated router on this network

>>No backup designated router on this network

// Correct. The first one is not working properly.

3. in Jerry's show ip ospf int a DR is seen is on the spoke and it is the hub router.

I cannot say what was the cause of the issue.

// No worry. I think it might be the router itself is causing the problem, as each lab is using different router to be hub and spoke. BTW: for the problematic lab, I do it for 7 times, and everytime it is same problem leading me to think it is nei statement problem.

The hub-spoke connection is fine, but spoke routers won't get routes from other ospf areas resulting the whole lab unfunctional.

Now, pretty much knowing the problem and their temporary or permanent fix for the lab sake.

I think this is the purpose of CCIE lab test letting you to play around as much as possible for the technologies: when it is working and when it is not working as well as different ways to accomplish the same task.

4. thanks Giuseppe, Jerry, Yang for the great help.

Have a good night to All.