OSPF Multi Area Configuration of 2 Routers – Class A – Advance LAB

In this lab, I will show you OSPF Multi Area Configuration of 2 Routers

VLSM

Given Network: 100.0.0.0

Host Requirement on Router 1: 10,00,000

Host Requirement on Router 2: 1,00,000

Router 1<= 10,00,000

10,00,000<= 2ⁿ – 2

10,00,000<= 2²⁰ – 2

10,00,000<= 10,48,576 – 2

10,00,000<= 10,48,574

Total number of network bit = 32

32 – n = 32 – 20 = 12 (CIDR of Router 1 network i.e. Given network)

i.e. 100.0.0.0/12

N.S.M = 11111111.11110000.00000000.00000000

                        = 255.240.0.0

Block Size        = 256 – N.S.M

                        = 256 – 240 = 16

Note: Add this block size in given network so that we can get our new network for Router 2.

so the new network is 100.16.0.0/?

Now find FVH, LVH and Broadcast address

Given Network	100	0	0	0
First Valid Host-FVH	100	0	0	1
Last Valid Host-LVH	100	15	255	254
Broadcast	100	15	255	255
New Network	100	16	0	0

Router 2<= 1,00,000

1,00,000 <= 2ⁿ – 2

1,00,000 <= 2¹⁷ – 2

1,00,000 <= 1,31,072 – 2

1,00,000 <= 1,31,070

Total number of network bits = 32

32 – n = 32 – 17 = 15 (CIDR of Router 2 network i.e. New network)

i.e. 100.16.0.0/15

N.S.M = 11111111.11111110.00000000.00000000

                        = 255.255.254.0

Block Size        = 256 – N.S.M

                        = 256 – 254 = 2

Note: Add this block size in given network so that we can get our new network for Router 1 and 2 (Virtual Network).

so the new network is 100.18.0.0/?

Now find FVH, LVH and Broadcast address

Given Network	100	16	0	0
First Valid Host-FVH	100	16	0	1
Last Valid Host-LVH	100	17	255	254
Broadcast	100	17	255	255
New Network	100	18	0	0

Router 1 and Router 2 <= 2 (we required only two IP to connect two routers)

2 <= 2ⁿ – 2

2 <= 2² – 2

2 <= 4 – 2

2 <= 2

Total number of network bits = 32

32 – n = 32 – 2 = 30 (CIDR of Virtual network (R1&R2))

i.e. 100.18.0.0/30

N.S.M = 11111111.11111111.11111111.11111100

                        = 255.255.255.252

Block Size        = 256 – N.S.M

                        = 256 – 252 = 4

Note: Add this block size in given network so that we can get our new network for Router 3. This network can be used in future.

so the new network is 100.18.0.4/?

Now find FVH, LVH and Broadcast address

Given Network	100	18	0	0
First Valid Host-FVH	100	18	0	1
Last Valid Host-LVH	100	18	0	2
Broadcast	100	18	0	3
New Network	100	18	0	4

Basic Configuration on Router 1

Router>enable Router#configure terminal Router(config)#hostname R1 R1(config)#interface fastEthernet 0/0 R1(config-if)#ip address 100.0.0.1 255.240.0.0 R1(config-if)#no shutdown R1(config-if)#exit   R1(config)#interface serial 0/0/0 R1(config-if)#ip address 100.18.0.1 255.255.255.252 R1(config-if)#clock rate 64000 R1(config-if)#no shutdown R1(config-if)#exit R1(config)#exit R1#write

Basic Configuration on Router 2

Router>enable Router#configure terminal Router(config)#hostname R2 R2(config)#interface fastEthernet 0/0 R2(config-if)#ip address 100.16.0.1 255.254.0.0 R2(config-if)#no shutdown R2(config-if)#exit   R2(config)#interface serial 0/1/0 R2(config-if)#ip address 100.18.0.2 255.255.255.252 R2(config-if)#no shutdown R2(config-if)#exit R2(config)#exit R2#write

OSPF Multi Area Configuration on Router 1

R1>enable R1#configure terminal R1(config)#router ospf 30 R1(config-router)#network 100.0.0.1           0.0.0.0             area 1 R1(config-router)#network 100.18.0.1         0.0.0.0             area 0 R1(config-router)#exit R1(config)#exit R1#write

OSPF Multi Area Configuration on Router 2

R2>enable R2#configure terminal R2(config)#router ospf 30 R2(config-router)#network 100.18.0.2         0.0.0.0             area 0 R2(config-router)#network 100.16.0.1         0.0.0.0             area 2 R2(config-router)#exit R2(config)#exit R2#write

Verification on Router 1

R1#show ip route      100.0.0.0/8 is variably subnetted, 3 subnets, 3 masks C       100.0.0.0/12 is directly connected, FastEthernet0/0 O IA    100.16.0.0/15 [110/65] via 100.18.0.2, 00:00:07, Serial0/0/0 C       100.18.0.0/30 is directly connected, Serial0/0/0

Verification on Router 2

R2#show ip route      100.0.0.0/8 is variably subnetted, 3 subnets, 3 masks O IA    100.0.0.0/12 [110/65] via 100.18.0.1, 00:00:25, Serial0/1/0 C       100.16.0.0/15 is directly connected, FastEthernet0/0 C       100.18.0.0/30 is directly connected, Serial0/1/0