OSPF Loopback IP not propogating into the NBMA network

ande0255

If you are familiar with Chris Bryants CCNA videos, I set up my home lab about exactly as he sets his up for his Frame Relay / OSPF videos, with a hub and 2 spoke NBMA network connected through a frame switch. I've attached a pic I drew of the topology for reference, as well as the show run for each router.

Quick breakdown of the NBMA network, R1 is the hub, with R2 and R3 serving at the spokes. Each router is connected to the frame switch via smart serial cable, R2 and R3 have an Ethernet segment connected to a 2950, all routers router have a loopback in its own area advertising via OSPF. All 3 routers in the NBMA can see eachothers loopbacks being advertised, everything pings, all good.

I then introduce R4 connected to R1 via smart serial cable, it is an 1841 series router where as R1/R2/R3 are 2600 series, and it's Lo4 IP of 4.4.4.4 will not propagate to any of the routers in the NBMA network. All routers see R4's serial interfaces network being advertised via 4.4.4.4, but none of them are putting 4.4.4.4 in their route table, even R1 despite the debugs showing the loopback is sending Hello's from that IP every 10 seconds:

R1#debug ip ospf hello
OSPF hello events debugging is on
R1#
*Mar 1 11:04:45.969: OSPF: Send hello to 224.0.0.5 area 100 on Serial0/1 from 100.100.100.1
R1#
*Mar 1 11:04:47.556: OSPF: Rcv hello from 4.4.4.4 area 100 from Serial0/1 100.100.100.2
*Mar 1 11:04:47.556: OSPF: End of hello processing


I've tried changing the Loopback IP on R4 to a different IP and adjusted ospf configs, set the interface as an ospf point-to-point manually per cisco forums, changed R1's loopback to be a higher IP in case that was the issue, and finally tried changing the subnet from a /30 to a /24 on the 100.100.100.0 network - Nothing is getting R4's loopback to propagate in other routers route table.

I've debugged the hell out of this, I have google fu'd the internet, I cannot understand why this is loopback is not propagating. Below is the show run from all 4 routers, as for some reason I can't attach a txt doc, if anyone has ideas I'd appreaciate it - this is driving me crazy that no command or change to the config is fixing the issue!

(The topology drawing shows 100.100.100.0/30, I changed it to /24 while tshooting and haven't changed it back yet)

Router Configs:

---

R1

---

R1#show run
Building configuration...

Current configuration : 1354 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$NGd4$0XlLftIz0t3gbyu5p0LxL.
!
no aaa new-model
!
resource policy
!
no network-clock-participate slot 1
no network-clock-participate wic 0
ip cef
!
!
!
!
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
interface Loopback1
ip address 1.1.1.1 255.255.255.255
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/0
ip address 172.12.123.1 255.255.255.0
encapsulation frame-relay
frame-relay map ip 172.12.123.2 122 broadcast
frame-relay map ip 172.12.123.3 123 broadcast
no frame-relay inverse-arp
frame-relay lmi-type cisco
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/1
ip address 100.100.100.1 255.255.255.0
!
router ospf 1
log-adjacency-changes
network 1.1.1.1 0.0.0.0 area 11
network 100.100.100.0 0.0.0.255 area 100
network 172.12.123.0 0.0.0.255 area 0
neighbor 172.12.123.2
neighbor 172.12.123.3
!
!
!
ip http server
no ip http secure-server
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
!
!
!
!
line con 0
exec-timeout 0 0
logging synchronous
line aux 0
line vty 0 4
password CCNP
logging synchronous
login
!
!
end

R1#

---

R2

---

R2#show run
Building configuration...

Current configuration : 1313 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R2
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$mnvX$6PUwncUgxnPosZrfejpQ20
!
no aaa new-model
!
resource policy
!
no network-clock-participate slot 1
no network-clock-participate wic 0
ip cef
!
!
!
!
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
interface Loopback2
ip address 2.2.2.2 255.255.255.255
!
interface FastEthernet0/0
ip address 172.12.23.2 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0
ip address 172.12.123.2 255.255.255.0
encapsulation frame-relay
ip ospf priority 0
frame-relay map ip 172.12.123.1 221 broadcast
frame-relay map ip 172.12.123.3 321
no frame-relay inverse-arp
frame-relay lmi-type cisco
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/1
no ip address
shutdown
!
router ospf 1
log-adjacency-changes
network 2.2.2.2 0.0.0.0 area 22
network 172.12.23.0 0.0.0.255 area 23
network 172.12.123.0 0.0.0.255 area 0
!
!
!
ip http server
no ip http secure-server
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
!
!
!
!
line con 0
exec-timeout 0 0
logging synchronous
line aux 0
line vty 0 4
password CCNP
logging synchronous
login
!
!
end

R2#

---

R3

---

R3#show run
Building configuration...

Current configuration : 1392 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R3
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$sgqE$XREr.Rk9cPaXEqLtX2WTg.
!
no aaa new-model
!
resource policy
!
no network-clock-participate slot 1
no network-clock-participate wic 0
ip cef
!
!
!
!
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
controller T1 0/0
framing sf
linecode ami
!
controller T1 0/1
framing sf
linecode ami
!
!
!
!
!
!
interface Loopback3
ip address 3.3.3.3 255.255.255.255
!
interface FastEthernet0/0
ip address 172.12.23.3 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/2
ip address 172.12.123.3 255.255.255.0
encapsulation frame-relay
ip ospf priority 0
no fair-queue
frame-relay map ip 172.12.123.2 321
frame-relay map ip 172.12.123.1 321 broadcast
no frame-relay inverse-arp
!
interface Serial0/3
no ip address
shutdown
!
router ospf 1
log-adjacency-changes
network 3.3.3.3 0.0.0.0 area 33
network 172.12.23.0 0.0.0.255 area 23
network 172.12.123.0 0.0.0.255 area 0
!
!
!
ip http server
no ip http secure-server
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
!
!
!
!
line con 0
exec-timeout 0 0
logging synchronous
line aux 0
line vty 0 4
password CCNP
logging synchronous
login
!
!
end

R3#

---

R4

---

R4#show run
Building configuration...

Current configuration : 1244 bytes
!
! Last configuration change at 15:19:24 UTC Sat Dec 19 2015
!
version 15.1
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R4
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$K795$0saD8bLeyCgPSqrg8sJh/0
!
no aaa new-model
dot11 syslog
ip source-route
!
!
!
!
ip cef
no ip domain lookup
no ipv6 cef
multilink bundle-name authenticated
!
!
!
!
!
license udi pid CISCO1841 sn FTX1210Z0AE
!
!
!
!
!
!
interface Loopback4
ip address 4.4.4.4 255.255.255.255
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/0/0
no ip address
shutdown
no fair-queue
clock rate 2000000
!
interface Serial0/0/1
ip address 100.100.100.2 255.255.255.0
clock rate 2000000
!
router ospf 1
log-adjacency-changes
network 4.4.4.4 0.0.0.0 area 44
network 100.100.100.0 0.0.0.255 area 100
!
ip forward-protocol nd
no ip http server
no ip http secure-server
!
!
!
!
!
!
control-plane
!
!
line con 0
exec-timeout 0 0
logging synchronous
line aux 0
line vty 0 4
password CCNP
logging synchronous
login
transport input all
!
scheduler allocate 20000 1000
end

R4#

ande0255

The thing that gets me, is R1 is receiving the advertisement for the serial interface via the loopback interface of 4.4.4.4, but it's not adding 4.4.4.4 to the route table or advertising it.

The only differences among the routers is the difference in series / model, R1 - R4 is point to point rather than Non_Broadcast, and it does not have an interface in Area 0.

Also after every change made I did 'clear ip ospf proc' on each router to update their tables, so re-establishing adj's is not the issue as far as I can see from debugs.

atorven

One of ospf's loop prevention mechanisms means that ABRs will not learn of Type 3s from other ABR except through area 0. Your problem is that loopback 4 is in area 44 whilst R4 has no interfaces in area 0 - There are 2 easy ways that you can fix this;
- Create a virtual link between R1 and R4
- Move loopback 4 into area 100

ande0255

Thank you for the info, I knew this had to be above a CCNA level issue, I'm trying to solidify the fundamentals before tackling ROUTE.

I got everything else working so I'll stick to using this router to practice VPN / ACL / NAT practice on router IOS's, I work with ASA's all day but so configuring them on a router is becoming foreign to me.

Thank you for putting my mind at ease about that, I troubleshot that for hours, by virtual link do you mean a SVI?

atorven

Assuming that the RID of R1 is 1.1.1.1 and R2 is 4.4.4.4 do the below under each ospf process;

On R1
area 100 virtual-link 4.4.4.4

On R4
area 100 virtual-link 1.1.1.1

Virtual links aren't SVIs but they kind of similar in that they both aren't physical interfaces but one major difference is that virtual links don't actually route any traffic.

Virtual links always belong to area 0, so by adding them to both routers you're actually extending area 0 to area 44, R4 will now have an interface in area 0 and R1 will learn of the Type 3s being advertised by R4 which in turn means that all the other areas will learn of that Type 3.

You should get started on ROUTE as the fundamentals are refreshed and aren't just glossed over, there is a lot to learn, most of it fun!

Good luck with your studies.

ande0255

Others at my work told me the same thing about just jumping into CCNP, I think I'll just go for it here since I'm already getting ahead of myself.

Thanks again for the info, and the advice, I'm just going to jump on ROUTE, I love learning the material, so I don't foresee it being a huge hurdle - +rep for you sir

chopsticks

Side track, may I know what do you use to setup this lab? Thanks.

ande0255

That is my rack as of now:

1 x 2509 router (access server)
4 x 2600 series routers (one with 4 WICs operating as the frame switch)
1 x 1841 router
1 x 2811 router
2 x 2950 switches
1 x 3550 switch

I've only actually used the 2811 for voice gateway studies as I work UC (phone) tickets as well, I forgot I had the T1 card in R3, I was wondering why that was in the 2611XM. I have a 3560 on the way as of tonight for SWITCH, but I'm just using a 2950 right now to add that Area 23 fast ethernet segment to the topology.

As I configure stuff, I keep notepad docs open for each individual device, that I add configs as I think of what I need for base configs for different protocols I'm working with. At this point I can just open notepad and type out a config to just copy and paste into a freshly write erased router, though I kept at typing them manually until I could jot configs that I could paste without router errors yelling at me when I paste the entire thing, once I can type the configs like a machine I just copy and paste new topologies for ospf / eigrp as they require different frame relay settings for route advertisements.

I love adding to my physical lab, I love cabling the stuff, it's a pain to haul around when you move a lot but my physical lab humming is for some reason a huge motivation to lab my ass off

chopsticks

That's neat! How much did you invest on them?

ande0255

I bought a lot of it years ago, so as I slowly piece it together it came out to over a grand, but the same routers and layer 3 switch that was $100-$150 3-4 years ago are now usually around $50. So once I finally get rid of this stuff, I may put it on craigslist to see if there is any interest, but I wouldn't bother with shipping.

I would probably just figure out which facility recycles this type of electronic and throw em out, but that day will probably be a long ways away until I full virtualize my lab, I really love working with physical gear.