OSPF Part 2

Objectives

Stubby area

Configuration of Stubby area, creating virtual link

Router 1

input commands

router ospf 1

 router-id 1.1.1.1

 log-adjacency-changes

 area 12 virtual-link 2.2.2.2

 area 17 stub no-summary

 area 17 default-cost 10

Explanation

router ospf 1

area 17 stub no-summery  (identification for the subb area)

area 17 default-cost 10   ( to make R1 a preferred exit for area 17)

area 12 virtual-link 2.2.2.2 (router ID for area 0 DR)

Router  2

router ospf 1

area 12 virtual-link 1.1.1.1 

Router 7

config t

router ospf 1

router id 7.7.7.7

network 129.186.35.7 0.0.0.0 area 73

network 10.7.7.7 0.0.0.0 area 73

area 73 virtual-link 3.3.3.3

area 17 stub no summary

area 17 default-cost 100

exit

int lo 0

ip ospf network point-to-point

Router 3

router ospf 1

area 73 virtual-link 7.7.7.7

Objective point 4

Router 7

int    f1/0

ip ospf pri 200

explanation 

ip ospf pri 200    (to assign R7 as DR for area 73)

OSPF Authentication

Router 2

router ospf 1

area 0 authentication message-digest

int s1/1.23 (interface conncted area 0)

ip ospf message-digest-key 1 md5 cisco

int s1/1.24

ip ospf message-digest-key 1 md5 cisco

router ospf 1

area 12 virtual-link 1.1.1.1 authentication message-digest-key 1 md5 cisco

Router 1

router ospf 1

area 12 virtual-link 2.2.2.2 authentication message-digest-key 1 md5 cisco

Router 3

router ospf 1

area 0 authentication message-digest

int s1/1

ip ospf message-digest-key 1 md5 cisco

router ospf 1

area 73 virtual-link 7.7.7.7 authentication message-digest-key 1 md5 cisco

Router 7

router ospf 1

area 73 virtual-link 3.3.3.3 authentication message-digest-key 1 md5 cisco

Router 4

router ospf 1

area 0 authentication message-digest

int s1/1

ip ospf message-digest-key 1 md5 cisco

Router 5

router ospf 1

area 0 authentication message-digest

int s1/1

ip ospf message-digest-key 1 md5 cisco

show commands

show ip ospf virtual-link