My Notes On Routing Protocols: OSPF Non-Broadcast (NBMA) Network Configuration:

OSPF Non-Broadcast (NBMA) Network Configuration:

Non-Broadcast:

Default Network type on Cisco routers.
Routers cannot discover neighbors automatically, thus manual neighbors must be configured. (it is enough if you just configure on the Hub)
Hellos are sent as Unicast.
DR/BDR elections happen.
Hub must be elected as DR as it has full connectivity to the spokes. And spokes cannot get elected as DR/BDR.
Need to set the priority to 0 on the Spoke’s interface.
Hello and Dead timers are 30/120

Interface configuration on the Hub, R1:

R1#show run int ser1/0

Building configuration...

Current configuration : 227 bytes

interface Serial1/0

ip address 10.1.1.1 255.255.255.0

encapsulation frame-relay

serial restart-delay 0

frame-relay map ip 10.1.1.2 102 broadcast

frame-relay map ip 10.1.1.3 103 broadcast

no frame-relay inverse-arp

end

R1#

Interface configuration on the Spoke, R2:

R2#show run int ser1/0

Building configuration...

Current configuration : 247 bytes

interface Serial1/0

ip address 10.1.1.2 255.255.255.0

encapsulation frame-relay

ip ospf priority 0 à OSPF priority configured to 0

serial restart-delay 0

frame-relay map ip 10.1.1.1 201 broadcast

frame-relay map ip 10.1.1.3 201 broadcast

no frame-relay inverse-arp

end

R2#

Interface configuration on the Spoke, R3:

R3#show run int ser1/0

Building configuration...

Current configuration : 247 bytes

interface Serial1/0

ip address 10.1.1.3 255.255.255.0

encapsulation frame-relay

ip ospf priority 0 à OSPF priority configured to 0

serial restart-delay 0

frame-relay map ip 10.1.1.1 301 broadcast

frame-relay map ip 10.1.1.2 301 broadcast

no frame-relay inverse-arp

end

R3#

OSPF configuration on Hub, R1:

R1#show run | begin router ospf 1

router ospf 1

router-id 1.1.1.1

log-adjacency-changes

network 1.1.1.1 0.0.0.0 area 0

network 10.1.1.1 0.0.0.0 area 0

neighbor 10.1.1.2 à Neighbors configured manually

neighbor 10.1.1.3 à Neighbors configured manually

OSPF configuration on Spoke, R2:

R2#show run | begin router ospf 1

router ospf 1

router-id 2.2.2.2

log-adjacency-changes

network 2.2.2.2 0.0.0.0 area 0

network 10.1.1.2 0.0.0.0 area 0

OSPF configuration on Spoke, R3:

R3#show run | begin router ospf 1

router ospf 1

router-id 3.3.3.3

log-adjacency-changes

network 3.3.3.3 0.0.0.0 area 0

network 10.1.1.3 0.0.0.0 area 0

We need not configure the network type as NBMA is already a default network type:

R1#show ip ospf int ser1/0

Serial1/0 is up, line protocol is up

Internet Address 10.1.1.1/24, Area 0

Process ID 1, Router ID 1.1.1.1, Network Type NON_BROADCAST, Cost: 64

Transmit Delay is 1 sec, State DR, Priority 1

Designated Router (ID) 1.1.1.1, Interface address 10.1.1.1

No backup designated router on this network

Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5

oob-resync timeout 120

Hello due in 00:00:19

Supports Link-local Signaling (LLS)

Index 1/1, flood queue length 0

Next 0x0(0)/0x0(0)

Last flood scan length is 1, maximum is 1

Last flood scan time is 0 msec, maximum is 4 msec

Neighbor Count is 2, Adjacent neighbor count is 2

Adjacent with neighbor 2.2.2.2

Adjacent with neighbor 3.3.3.3

Suppress hello for 0 neighbor(s)

R1#

R1#show ip ospf nei

Neighbor ID Pri State Dead Time Address Interface

2.2.2.2 0 FULL/DROTHER 00:01:41 10.1.1.2 Serial1/0

3.3.3.3 0 FULL/DROTHER 00:01:31 10.1.1.3 Serial1/0

R1#

R2#show ip ospf nei

Neighbor ID Pri State Dead Time Address Interface

1.1.1.1 1 FULL/DR 00:01:32 10.1.1.1 Serial1/0

R2#

R3#show ip ospf nei

Neighbor ID Pri State Dead Time Address Interface

1.1.1.1 1 FULL/DR 00:01:46 10.1.1.1 Serial1/0

R3#

Routing Table:

R1#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

1.0.0.0/32 is subnetted, 1 subnets

C 1.1.1.1 is directly connected, Loopback0

2.0.0.0/32 is subnetted, 1 subnets

O 2.2.2.2 [110/65] via 10.1.1.2, 00:27:06, Serial1/0

3.0.0.0/32 is subnetted, 1 subnets

O 3.3.3.3 [110/65] via 10.1.1.3, 00:27:06, Serial1/0

10.0.0.0/24 is subnetted, 1 subnets

C 10.1.1.0 is directly connected, Serial1/0

R1#

R2#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

1.0.0.0/32 is subnetted, 1 subnets

O 1.1.1.1 [110/65] via 10.1.1.1, 00:27:28, Serial1/0

2.0.0.0/32 is subnetted, 1 subnets

C 2.2.2.2 is directly connected, Loopback0

3.0.0.0/32 is subnetted, 1 subnets

O 3.3.3.3 [110/65] via 10.1.1.3, 00:27:28, Serial1/0 àNext-hop is R3

10.0.0.0/24 is subnetted, 1 subnets

C 10.1.1.0 is directly connected, Serial1/0

R2#

R2#ping 3.3.3.3

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 24/73/148 ms
R2#

R3#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

1.0.0.0/32 is subnetted, 1 subnets

O 1.1.1.1 [110/65] via 10.1.1.1, 00:27:43, Serial1/0

2.0.0.0/32 is subnetted, 1 subnets

O 2.2.2.2 [110/65] via 10.1.1.2, 00:27:43, Serial1/0 à Next-hop is R2

3.0.0.0/32 is subnetted, 1 subnets

C 3.3.3.3 is directly connected, Loopback0

10.0.0.0/24 is subnetted, 1 subnets

C 10.1.1.0 is directly connected, Serial1/0

R3#

R3#ping 2.2.2.2

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 2.2.2.2, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 12/70/168 ms

R3#

Debugs from R1:

*Jun 14 20:31:40.903: OSPF: Interface Serial1/0 going Up

*Jun 14 20:31:41.403: OSPF: Build router LSA for area 0, router ID 1.1.1.1, seq 0x80000001

*Jun 14 20:31:51.623: OSPF: Interface Loopback0 going Up

*Jun 14 20:31:52.127: OSPF: Build router LSA for area 0, router ID 1.1.1.1, seq 0x80000002

*Jun 14 20:32:37.519: OSPF: Starting 0.0.0.0 address 10.1.1.2 on Serial1/0

*Jun 14 20:32:40.419: OSPF: Starting 0.0.0.0 address 10.1.1.3 on Serial1/0

*Jun 14 20:33:40.903: OSPF: end of Wait on interface Serial1/0

*Jun 14 20:33:40.903: OSPF: DR/BDR election on Serial1/0

*Jun 14 20:33:40.903: OSPF: Elect BDR 1.1.1.1

*Jun 14 20:33:40.903: OSPF: Elect DR 1.1.1.1

*Jun 14 20:33:40.903: OSPF: Elect BDR 0.0.0.0

*Jun 14 20:33:40.907: OSPF: Elect DR 1.1.1.1

*Jun 14 20:33:40.907: DR: 1.1.1.1 (Id) BDR: none

*Jun 14 20:33:40.907: OSPF: Starting 0.0.0.0 address 10.1.1.2 on Serial1/0

*Jun 14 20:33:40.907: OSPF: Starting 0.0.0.0 address 10.1.1.3 on Serial1/0

*Jun 14 20:33:40.911: OSPF: Send hello to 10.1.1.2 area 0 on Serial1/0 from 10.1.1.1

*Jun 14 20:33:40.911: OSPF: Send hello to 10.1.1.3 area 0 on Serial1/0 from 10.1.1.1

*Jun 14 20:33:40.999: OSPF: Rcv hello from 3.3.3.3 area 0 from Serial1/0 10.1.1.3

*Jun 14 20:33:40.999: OSPF: 2 Way Communication to 3.3.3.3 on Serial1/0, state 2WAY

*Jun 14 20:33:41.003: OSPF: Neighbor change Event on interface Serial1/0

*Jun 14 20:33:41.003: OSPF: DR/BDR election on Serial1/0

*Jun 14 20:33:41.003: OSPF: Elect BDR 0.0.0.0

*Jun 14 20:33:41.003: OSPF: Elect DR 1.1.1.1

*Jun 14 20:33:41.003: DR: 1.1.1.1 (Id) BDR: none

*Jun 14 20:33:41.007: OSPF: Send DBD to 3.3.3.3 on Serial1/0 seq 0x1CE8 opt 0x52 flag 0x7 len 32

*Jun 14 20:33:41.007: OSPF: End of hello processing

*Jun 14 20:33:41.007: OSPF: Rcv hello from 2.2.2.2 area 0 from Serial1/0 10.1.1.2

*Jun 14 20:33:41.011: OSPF: 2 Way Communication to 2.2.2.2 on Serial1/0, state 2WAY

*Jun 14 20:33:41.011: OSPF: Neighbor change Event on interface Serial1/0

*Jun 14 20:33:41.011: OSPF: DR/BDR election on Serial1/0

*Jun 14 20:33:41.011: OSPF: Elect BDR 0.0.0.0

*Jun 14 20:33:41.011: OSPF: Elect DR 1.1.1.1

*Jun 14 20:33:41.011: DR: 1.1.1.1 (Id) BDR: none

*Jun 14 20:33:41.015: OSPF: Send DBD to 2.2.2.2 on Serial1/0 seq 0x10C2 opt 0x52 flag 0x7 len 32

*Jun 14 20:33:41.015: OSPF: End of hello processing

*Jun 14 20:33:41.043: OSPF: Rcv DBD from 3.3.3.3 on Serial1/0 seq 0xBCE opt 0x52 flag 0x7 len 32 mtu 1500 state EXSTART

*Jun 14 20:33:41.047: OSPF: NBR Negotiation Done. We are the SLAVE

*Jun 14 20:33:41.047: OSPF: Send DBD to 3.3.3.3 on Serial1/0 seq 0xBCE opt 0x52 flag 0x2 len 52

*Jun 14 20:33:41.047: OSPF: Rcv DBD from 2.2.2.2 on Serial1/0 seq 0x7A2 opt 0x52 flag 0x7 len 32 mtu 1500 state EXSTART

*Jun 14 20:33:41.051: OSPF: NBR Negotiation Done. We are the SLAVE

*Jun 14 20:33:41.051: OSPF: Send DBD to 2.2.2.2 on Serial1/0 seq 0x7A2 opt 0x52 flag 0x2 len 52

*Jun 14 20:33:41.071: OSPF: Rcv DBD from 3.3.3.3 on Serial1/0 seq 0xBCF opt 0x52 flag 0x3 len 52 mtu 1500 state EXCHANGE

*Jun 14 20:33:41.075: OSPF: Send DBD to 3.3.3.3 on Serial1/0 seq 0xBCF opt 0x52 flag 0x0 len 32

*Jun 14 20:33:41.075: OSPF: Rcv DBD from 2.2.2.2 on Serial1/0 seq 0x7A3 opt 0x52 flag 0x3 len 52 mtu 1500 state EXCHANGE

*Jun 14 20:33:41.075: OSPF: Send DBD to 2.2.2.2 on Serial1/0 seq 0x7A3 opt 0x52 flag 0x0 len 32

*Jun 14 20:33:41.099: OSPF: Rcv DBD from 3.3.3.3 on Serial1/0 seq 0xBD0 opt 0x52 flag 0x1 len 32 mtu 1500 state EXCHANGE

*Jun 14 20:33:41.099: OSPF: Exchange Done with 3.3.3.3 on Serial1/0

*Jun 14 20:33:41.099: OSPF: Send LS REQ to 3.3.3.3 length 12 LSA count 1

*Jun 14 20:33:41.099: OSPF: Send DBD to 3.3.3.3 on Serial1/0 seq 0xBD0 opt 0x52 flag 0x0 len 32

*Jun 14 20:33:41.103: OSPF: Rcv LS REQ from 3.3.3.3 on Serial1/0 length 36 LSA count 1

*Jun 14 20:33:41.103: OSPF: Send UPD to 10.1.1.3 on Serial1/0 length 52 LSA count 1

*Jun 14 20:33:41.107: OSPF: Rcv DBD from 2.2.2.2 on Serial1/0 seq 0x7A4 opt 0x52 flag 0x1 len 32 mtu 1500 state EXCHANGE

*Jun 14 20:33:41.107: OSPF: Exchange Done with 2.2.2.2 on Serial1/0

*Jun 14 20:33:41.107: OSPF: Send LS REQ to 2.2.2.2 length 12 LSA count 1

*Jun 14 20:33:41.111: OSPF: Send DBD to 2.2.2.2 on Serial1/0 seq 0x7A4 opt 0x52 flag 0x0 len 32

*Jun 14 20:33:41.111: OSPF: Rcv LS REQ from 2.2.2.2 on Serial1/0 length 36 LSA count 1

*Jun 14 20:33:41.115: OSPF: Send UPD to 10.1.1.2 on Serial1/0 length 52 LSA count 1

*Jun 14 20:33:41.135: OSPF: Rcv LS UPD from 3.3.3.3 on Serial1/0 length 76 LSA count 1

*Jun 14 20:33:41.139: OSPF: Synchronized with 3.3.3.3 on Serial1/0, state FULL

*Jun 14 20:33:41.139: %OSPF-5-ADJCHG: Process 1, Nbr 3.3.3.3 on Serial1/0 from LOADING to FULL, Loading Done

*Jun 14 20:33:41.147: OSPF: Rcv LS UPD from 2.2.2.2 on Serial1/0 length 76 LSA count 1

*Jun 14 20:33:41.147: OSPF: Synchronized with 2.2.2.2 on Serial1/0, state FULL

*Jun 14 20:33:41.151: %OSPF-5-ADJCHG: Process 1, Nbr 2.2.2.2 on Serial1/0 from LOADING to FULL, Loading Done

*Jun 14 20:34:10.911: OSPF: Send hello to 10.1.1.2 area 0 on Serial1/0 from 10.1.1.1

*Jun 14 20:34:10.911: OSPF: Send hello to 10.1.1.3 area 0 on Serial1/0 from 10.1.1.1

R1(config-router)#

My Notes On Routing Protocols

Thursday 14 June 2012

OSPF Non-Broadcast (NBMA) Network Configuration:

No comments:

Post a Comment

Labels

About Me

My Notes On Routing Protocols