<Jeremy's IT Lab> Day 28: OSPF (part 3)

OSPF (part 3)

 

Loop back: virtual int (defualt up/up state; provide consistent IP adrs)

 

Type of OSPF:

1. broad cast

- default on Ethernet, FDDI(Fiber Distributed Data Interface)

-> use multicast adrs <224.0.0.5>

-> DR/ BDR must be elected each subnet (if no OSPF, DR only)

-> Neither DR/BDR, DROther (2-way state; not exchange LSAs)

-> when DR goes down, BDR becomes DR (regardlness DROther's priority)

-> priority:

   (1) highest OSPF int priority (default 1)

   (2) highest OSPF Router ID

-> hello 10 sec, dead time 40 sec

 

2. Point-to-Point (legacy)

- default on PPP(point to point protocol), HDLC(High-level Data link Control)

-> use multicast adrs <224.0.0.5>

-> L2 encapsulation

-> DR/BDR not elected

-> One side DCE(Data Communications Equipment), other side DTE(Data Termianl Equipment)

-> router formed full adjacency

-> // clock rate (diff btw speed in Ethernet protocol)

-> hello 10 sec, dead time 40 sec

 

3. Non-broadcast

- default on Frame Relay, X.25 (out of CCNA)

-> hello 30 sec, dead time 120 sec

 

OSPF Requirment:

1. Must match Area Number | Subnet(area) |  Hello, Dead timers | Authentication setting | IP MTU | OSPF NW Type

2. Must be unnique OSPF ID

 

OSPF LSA Types:

-> LSDB made of LSA

-> 11 types (CCNA only handle 3)

->types:

   (1) Type 1(Router LSA)

       - all router generated

       - identifies Router ID

       - list NW attached to Router's OSPF-activated int

   (2) Type 2(NW LSA)

       - generated by DR

       - list routers which attached to multi access NW

(3) Type 3(AS-External LSA)

       - generated by ASBR

 

CLI//

R1#sh ip int br

Interface IP-Address OK? Method Status Protocol

GigabitEthernet0/0 10.0.1.254 YES manual up up

GigabitEthernet0/1 unassigned YES unset administratively down down

GigabitEthernet0/2 unassigned YES unset administratively down down

Serial0/0/0 unassigned YES unset administratively down down

Serial0/0/1 unassigned YES unset administratively down down

Vlan1 unassigned YES unset administratively down down

R1#conf t

Enter configuration commands, one per line. End with CNTL/Z.

R1(config)#int s0/0/0

R1(config-if)#ip add 192.168.12.1 255.255.255.252

R1(config-if)#do show controllers s0/0/0

Interface Serial0/0/0

Hardware is PowerQUICC MPC860

DCE V.35, clock rate 2000000

...

R1(config-if)#clock rate 128000

R1(config-if)#no shut

%LINK-5-CHANGED: Interface Serial0/0/0, changed state to down

-

R2(config-if)#do sh contr s0/0/0

Interface Serial0/0/0

Hardware is PowerQUICC MPC860

DTE V.35 TX and RX clocks detected

-

R1(config)#int s0/0/0

R1(config-if)#ip ospf 1 area 0

R1(config-if)#

00:30:36: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.245.1 on Serial0/0/0 from LOADING to FULL, Loading Done

int g0/0

R1(config-if)#ip ospf 1 area 0

R1(config-if)#do sh ip ospf int s0/0/0

 

Serial0/0/0 is up, line protocol is up

Internet address is 192.168.12.1/30, Area 0

Process ID 1, Router ID 192.168.12.1, Network Type POINT-TO-POINT, Cost: 64

Transmit Delay is 1 sec, State POINT-TO-POINT,

 

R1(config-if)#do sh ip ospf int g0/0

 

GigabitEthernet0/0 is up, line protocol is up

Internet address is 10.0.1.254/24, Area 0

Process ID 1, Router ID 192.168.12.1, Network Type BROADCAST, Cost: 1

Transmit Delay is 1 sec, State DR, Priority 1

Designated Router (ID) 192.168.12.1, Interface address 10.0.1.254

 

R2(config-if)#do sh ip ospf neigh

 

 

Neighbor ID Pri State Dead Time Address Interface

192.168.12.1 0 FULL/ - 00:00:38 192.168.12.1 Serial0/0/0

192.168.245.2 1 FULL/DR 00:00:35 192.168.245.2 GigabitEthernet0/0

 

R5#sh ip ospf int g0/0

 

GigabitEthernet0/0 is up, line protocol is up

Internet address is 192.168.245.3/29, Area 0

Process ID 1, Router ID 203.0.113.1, Network Type BROADCAST, Cost: 1

Transmit Delay is 1 sec, State DR, Priority 1

Designated Router (ID) 203.0.113.1, Interface address 192.168.245.3

No backup designated router on this network

Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5

Hello due in 00:00:02

Index 1/1, flood queue length 0

## doesn't match with R2 & R4

 

R5(config)#int g0/0

R5(config-if)#no ip ospf hello-interval

R5(config-if)#no ip ospf dead-interval

R5(config-if)#do sh ip ospf int g0/0

 

GigabitEthernet0/0 is up, line protocol is up

Internet address is 192.168.245.3/29, Area 0

Process ID 1, Router ID 203.0.113.1, Network Type BROADCAST, Cost: 1

Transmit Delay is 1 sec, State DR, Priority 1

Designated Router (ID) 203.0.113.1, Interface address 192.168.245.3

Backup Designated Router (ID) 192.168.245.1, Interface address 192.168.245.1

Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5

 

 

R5(config-if)#do sh ip ospf neigh

 

 

Neighbor ID Pri State Dead Time Address Interface

192.168.245.1 1 FULL/BDR 00:00:31 192.168.245.1 GigabitEthernet0/0

192.168.245.2 1 FULL/DROTHER 00:00:30 192.168.245.2 GigabitEthernet0/0

R5(config-if)#

R5(config-if)#do sh run | section ospf

router ospf 1

log-adjacency-changes

network 192.168.245.3 0.0.0.0 area 0

default-information originate

R5(config-if)#do sh ip route

Codes: L - local, 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, E - EGP

i - IS-IS, 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

 

10.0.0.0/24 is subnetted, 2 subnets

O 10.0.1.0/24 [110/66] via 192.168.245.1, 00:02:42, GigabitEthernet0/0

O 10.0.2.0/24 [110/3] via 192.168.245.2, 00:02:42, GigabitEthernet0/0

192.168.12.0/30 is subnetted, 1 subnets

O 192.168.12.0/30 [110/65] via 192.168.245.1, 00:02:42, GigabitEthernet0/0

192.168.34.0/30 is subnetted, 1 subnets

O 192.168.34.0/30 [110/2] via 192.168.245.2, 00:02:42, GigabitEthernet0/0

192.168.245.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.245.0/29 is directly connected, GigabitEthernet0/0

L 192.168.245.3/32 is directly connected, GigabitEthernet0/0

203.0.113.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.0.113.0/30 is directly connected, GigabitEthernet0/0/0

L 203.0.113.1/32 is directly connected, GigabitEthernet0/0/0

---> no default routing

R5(config-if)#exit

R5(config)#ip route 0.0.0.0 0.0.0.0 203.0.113.2

## create default route

 

R1(config)#do sh ip route

Codes: L - local, 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, E - EGP

i - IS-IS, 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 192.168.12.2 to network 0.0.0.0

 

10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks

C 10.0.1.0/24 is directly connected, GigabitEthernet0/0

L 10.0.1.254/32 is directly connected, GigabitEthernet0/0

O 10.0.2.0/24 [110/67] via 192.168.12.2, 00:12:02, Serial0/0/0

192.168.12.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.12.0/30 is directly connected, Serial0/0/0

L 192.168.12.1/32 is directly connected, Serial0/0/0

192.168.34.0/30 is subnetted, 1 subnets

O 192.168.34.0/30 [110/66] via 192.168.12.2, 00:17:03, Serial0/0/0

192.168.245.0/29 is subnetted, 1 subnets

O 192.168.245.0/29 [110/65] via 192.168.12.2, 00:04:38, Serial0/0/0

O*E2 0.0.0.0/0 [110/1] via 192.168.12.2, 00:01:32, Serial0/0/0

 

R1(config)#do sh ip ospf database

OSPF Router with ID (192.168.12.1) (Process ID 1)

 

Router Link States (Area 0)

 

Link ID ADV Router Age Seq# Checksum Link count

192.168.12.1 192.168.12.1 1074 0x80000003 0x00f081 3

192.168.34.1 192.168.34.1 784 0x80000008 0x00ec11 2

192.168.245.1 192.168.245.1 351 0x80000006 0x004a83 3

203.0.113.1 203.0.113.1 347 0x80000004 0x00848a 1

192.168.245.2 192.168.245.2 347 0x80000008 0x005e3e 2

 

Net Link States (Area 0)

Link ID ADV Router Age Seq# Checksum

192.168.34.2 192.168.245.2 1065 0x80000004 0x00f525

192.168.245.3 203.0.113.1 347 0x80000002 0x00892d

 

Type-5 AS External Link States

Link ID ADV Router Age Seq# Checksum Tag

0.0.0.0 203.0.113.1 158 0x80000001 0x00d2c1 1