Junos Basic OSPF configuration

This tutorial will show basic OSPF configuration on JUNOS- Juniper router.

Only 2 routers in area 0 with back to back interface as per diagram below, basic interface configuration for IPV4 also will be show here for the requirement before proceed to OSPF configuration.

R1:

Interface configuration:

set interfaces em1 unit 0 family inet address 172.16.0.1/30
set interfaces lo0 unit 0 family inet address 10.0.0.1/32

OSPF configuration:

set protocols ospf area 0.0.0.0 interface em1.0
set protocols ospf area 0.0.0.0 interface lo0.0 passive

For loopback interface passive was configured since loopback interface does not require to perform adjacency with other router, so no hello packet is require to be send.

R1:

Interface configuration:

set interfaces em1 unit 0 family inet address 172.16.0.2/30
set interfaces lo0 unit 0 family inet address 10.0.0.2/32

OSPF configuration:

set protocols ospf area 0.0.0.0 interface em1.0
set protocols ospf area 0.0.0.0 interface lo0.0 passive

Verification step:

Verify the reachabality using Ping command:

user01@lab-r2# run ping rapid 172.16.0.1 count 5PING 172.16.0.1 (172.16.0.1): 56 data bytes!!!!!--- 172.16.0.1 ping statistics ---5 packets transmitted, 5 packets received, 0% packet lossround-trip min/avg/max/stddev = 0.509/0.626/0.862/0.123 ms

Verify the neighbor-ship of OSPF:

user01@lab-r2# run show ospf interface
Interface           State   Area            DR ID           BDR ID          Nbrs
em1.0               DR      0.0.0.0         10.0.0.2        10.0.0.1           1
lo0.0               DRother 0.0.0.0         0.0.0.0         0.0.0.0            0

It's verified that OSPF have been established with Nbrs(neighbors) = 1, Lab-R2 interface em1.0 is DR(designated router) for the relationship is Lab-R1 E1

run show ospf neighbor
Address          Interface              State     ID               Pri  Dead
172.16.0.1       em1.0                  Full      10.0.0.1         128    38