OSPF Lab 1

Tasks:

1.  Enable OSPF on the routers .All the interfaces should belong to area 0. Do not use the network statement
on R3. Prevent secondary addresses on R2 from being advertised into the OSPF domain.
The  router id should be statically configured.
R1 should not be a neighbor of R2. Do not use ip ospf network command.

2.    R2 should send hello packet every 2 seconds out the interface F0/1.

3.    R1 should send hello packet to R3 every 250 ms.

4.    R1 and R3 should send updates through the serial link when there is a change.

5.    The time between link-state advertisement (LSA) retransmissions for adjacencies belonging to R3 F0/1 interface should be 8 seconds

6.    The estimated time required to send a link-state update packet on R1 F0/1 interface is 3 seconds.

Lab Diagram:

NB: Click here to download the .net file and the initial configuration files.

Solutions:

Task 1:

R1:
Interface FastEthernet0/0
ip ospf priority 0

router ospf 1
router-id 1.1.1.1
network 33.33.1.1 0.0.0.0 area 0
network 33.33.13.1 0.0.0.0 area 0
network 33.33.123.1 0.0.0.0 area 0

R2:
router ospf 1
router-id 2.2.2.2

interface FastEthernet0/0
ip ospf priority 0
ip ospf 1 area 0 secondaries none

interface FastEthernet0/1
ip ospf 1 area 0 secondaries none

R3:
router ospf 1
router-id 3.3.3.3

interface FastEthernet0/0
ip ospf 1 area 0
!
interface FastEthernet0/1
ip ospf 1 area 0

interface Serial1/0
ip ospf 1 area 0

Verification:

R1#show ip ospf neighbor
Neighbor ID     Pri   State           Dead Time   Address         Interface
3.3.3.3           0   FULL/  -        840 msec    33.33.13.3      Serial1/0
2.2.2.2           0   2WAY/DROTHER 00:00:35    33.33.123.2     FastEthernet0/0
3.3.3.3           1   FULL/DR         00:00:39    33.33.123.3     FastEthernet0/0

R1#show ip route ospf
33.0.0.0/24 is subnetted, 5 subnets
O       33.33.2.0 [110/2] via 33.33.123.2, 00:06:41, FastEthernet0/0
O       33.33.3.0 [110/2] via 33.33.123.3, 00:06:41, FastEthernet0/0

R2#sh ip ospf neighbor
Neighbor ID     Pri   State           Dead Time   Address         Interface
1.1.1.1           0   2WAY/DROTHER 00:00:30    33.33.123.1     FastEthernet0/0
3.3.3.3           1   FULL/DR         00:00:30    33.33.123.3     FastEthernet0/0

R2#sh 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

2.0.0.0/24 is subnetted, 1 subnets
C       2.2.2.0 is directly connected, FastEthernet0/1  // Secondary address not advertised
33.0.0.0/24 is subnetted, 5 subnets
O       33.33.1.0 [110/2] via 33.33.123.1, 00:06:17, FastEthernet0/0
C       33.33.2.0 is directly connected, FastEthernet0/1
O       33.33.3.0 [110/2] via 33.33.123.3, 00:06:17, FastEthernet0/0
O       33.33.13.0 [110/65] via 33.33.123.3, 00:06:17, FastEthernet0/0
[110/65] via 33.33.123.1, 00:06:17, FastEthernet0/0
C       33.33.123.0 is directly connected, FastEthernet0/0
22.0.0.0/24 is subnetted, 1 subnets
C       22.22.22.0 is directly connected, FastEthernet0/0 // Secondary address not advertised

R3#show ip ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface
1.1.1.1           0   FULL/  -        976 msec    33.33.13.1      Serial1/0
1.1.1.1           0   FULL/DROTHER    00:00:32    33.33.123.1     FastEthernet0/0
2.2.2.2           0   FULL/DROTHER    00:00:37    33.33.123.2     FastEthernet0/0

R3#show ip route ospf
33.0.0.0/24 is subnetted, 5 subnets
O       33.33.1.0 [110/2] via 33.33.123.1, 00:06:53, FastEthernet0/0
O       33.33.2.0 [110/2] via 33.33.123.2, 00:06:53, FastEthernet0/0

Task 2:

R2:
interface FastEthernet0/1
ip ospf hello-interval 2

Verification:

R2#show ip ospf interface f0/1
FastEthernet0/1 is up, line protocol is up
…….. omitted output
No backup designated router on this network
Timer intervals configured, Hello 2, Dead 8, Wait 8, Retransmit 5
…….. omitted output

Task 3:

R1 & R3:
Interface Serial 1/0
ip ospf dead-interval minimal hello-multiplier 4

Verification:

R3#show ip ospf interface s1/0
Serial1/0 is up, line protocol is up
…….. omitted output
Timer intervals configured, Hello 250 msec, Dead 1, Wait 1, Retransmit 5

R1#show ip ospf interface s1/0
Serial1/0 is up, line protocol is up
…….. omitted output
Timer intervals configured, Hello 250 msec, Dead 1, Wait 1, Retransmit 5

Task 4:

R3:
interface Serial1/0
ip ospf demand-circuit

Verification:

R1#show ip ospf interface s1/0
Serial1/0 is up, line protocol is up
…….. omitted output
Run as demand circuit.
DoNotAge LSA allowed.
…….. omitted output

R1#show ip ospf interface s1/0
…….. omitted output
Run as demand circuit.
DoNotAge LSA allowed.
…….. omitted output

Task 5:

R3:
interface fastEthernet 0/1
ip ospf retransmit-interval 8

Verification:

R3#show ip ospf interface f0/1
FastEthernet0/0 is up, line protocol is up
…….. omitted output
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 8
…….. omitted output

Task 6:

R1:
interface fastEthernet 0/1
ip ospf transmit-delay 3

Verification:

R1#show ip ospf interface f0/1
…….. omitted output
Transmit Delay is 3 sec, State DR, Priority 1
…….. omitted output